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The mission of AFTA is to promote the wider adoption of agroforestry by landowners in temperate regions of North America. Formed in 1991, the Association for Temperate Agroforestry Inc. (AFTA) is a private, non-profit, 501(c)(3) organization based at the University of Missouri Center for Agroforestry at Columbia.
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A National Strategy to Develop and Implement Agroforestry
Produced by a Workshop to "Develop a Framework for a Coordinated National Agroforestry Program,"
June 29-30, 1994 Nebraska City, Nebraska
| Executive Summary | What is Agroforestry? |
| Background | Status of Agroforestry Development |
| Needs & Opportunities | Trends Affecting Agroforestry |
| Recommendations | Workshop Participants |
Agroforestry, the intentional integration of agricultural and forestry-based land-use systems, provides multiple benefits that collectively contribute to agroecosystem sustainability. Agroforestry addresses the nation's land stewardship needs by converting degraded lands, protecting sensitive lands, and diversifying farm production systems. As part of an ecologically-based land management system, agroforestry practices can maintain ecosystem diversity and processes that contribute to long-term sustainability and environmental quality.
This white paper identifies unique needs and recommends actions to develop and implement agroforestry nationally. The recommended actions for agroforestry are supported by a unified community of interest.
Although there is strong interest and potential for agroforestry to help achieve many sustainability goals, agroforestry development and implementation is impeded because it is non-traditional, lacks recognition, and cuts across agencies, programs, and disciplines. Present programs are neither designed nor funded sufficiently to deal with agroforestry. Specifically, getting agroforestry accepted and applied requires technology development and integration, application and decision-support tools, technology transfer to agriculture and natural resource professionals, and technical assistance to landowners. The immediate need is to get agroforestry on the ground through a concerted effort to get into practice what is already known and to coordinate and strengthen the development of new knowledge.
Recommendations for accomplishing these goals are: (1) Establish an agroforestry subtitle in the 1995 farm bill to address agroforestry's unique opportunities, needs and challenges; (2) Establish a USDA interagency coordinating committee and a national coordinator for agroforestry; (3) Establish regional agroforestry organizations to enhance linkages and information exchange; (4) Establish a national agroforestry advisory council; (5) Establish a national interagency agroforestry center and clearinghouse for agroforestry cooperation; (6) Provide focused funding for agroforestry research, development, applications, demonstrations, technology transfer, and training; (7) Increase emphasis on field and landscape buffer zones; and (8) Increase emphasis on international agroforestry technology exchange.
Agroforestry is an unprecedented opportunity for interagency cooperation. At this juncture, it is critical that national interagency leadership be provided from within USDA. A "Team USDA" effort is necessary for success.
Agroforestry is the intentional integration of agricultural and forestry-based land-use systems to provide tree and other crop products, and at the same time protect, conserve, diversify, and sustain vital economic, environmental, human, and natural resources. Four key principles in agroforestry are: (1) trees and/or shrubs are deliberately combined with crops and/or livestock; (2) land use is intensive; (3) biological interactions are increased; and (4) benefits are optimized. Agroforestry includes windbreaks planted into production agriculture systems, but it also includes the intentional growing of an understory high-value specialty crop of ginseng under the protection of forest cover. Agroforestry is "working trees"-the right trees and shrubs planted and/or managed in the right place to do a specific job. Agroforestry practices include windbreaks, alley cropping, tree/pasture systems, living snowfences, riparian forest buffers, tree/specialty crop systems, forest/specialty crop systems (forest farming), wildlife habitat, and fuelwood plantations.
In view of the environmental problems confronting modern agriculture, and the emphasis being placed on developing sustainable agricultural and natural resource systems, agroforestry can have lasting economic, environmental, and social impacts. As part of an ecologically-based land management system, agroforestry practices can contribute substantially to generating the ecosystem diversity and processes important to long-term sustainability. At farm, watershed, and landscape scales, integration of agroforestry practices can transform our agricultural lands into stable, resilient, diverse, aesthetic, and sustainable agricultural land-use systems. Agroforestry practices can increase crop production, control erosion and sediment, provide multiple crops including wood products, sequester and biodegrade excess nutrients and pesticides, moderate microclimates, and diversify habitats for wildlife and humans. Agroforestry systems sequester carbon and serve as a renewable energy source. By enhancing the production capabilities of rural lands, agroforestry can help revitalize rural communities that have become socially depressed due to recent "economic downturns".
Agroforestry offers the opportunity to address some of our nation's, indeed our world's, most complex problems, and thereby constitutes an arena in which a host of stakeholders can come together in developing a common agenda for conservation and land-use practices. A "first step" toward that common agenda was accomplished with the February, 1994 publication of the Soil Conservation Service's (SCS), Resource Conservation Act (RCA) appraisal for agroforestry entitled: "Agroforestry: an Intergrated Land-Use Management System for Production and Farmland Conservation". The awareness created by the RCA document resulted in a workshop held June 29-30, 1994 to assemble stakeholders to "Develop a framework for a coordinated national agroforestry program". The participants, representing federal and state agencies, universities, and non-government organizations (NGO) from across the U.S., and the Association for Temperate Agroforestry (AFTA), assembled to define and address the unique needs and challenges of agroforestry, and develop the recommendations in this white paper. With the unified support of this community of interest, and that of peers and other interested parties, it is hoped that together we can "make a difference" for agroforestry and the vitality of rural America. The American public is demanding new approaches to the management of our nation's farm and forest lands -- agroforestry offers a viable option to conventional approaches.
However, while factors that are important to its development are beginning to converge, the benefits of agroforestry will not be fully realized without focused policies, programs, funding, and interdisciplinary teams. Present programs are neither designed nor funded sufficiently to deal with a "cross-cutting" science and practice like agroforestry. The infrastructure required must be established with the ultimate user, the landowner, at the center, and be designed to promote a continuous process of innovation. This will require a concerted team effort on the part of many, including established agriculture and natural resource institutions such as USDA agencies and land-grant universities. At this juncture, it is especially critical that national leadership be provided from within USDA.
Furthermore, the formulation of the 1995 Farm Bill offers an important opportunity to institutionalize agroforestry development at the federal level as part of a strategy to reduce the, public cost of resource conservation, to provide better customer service, and to develop more environmentally and socially sustainable agricultural production systems.
Status of Agroforestry Development
There is a groundswell of interest in agroforestry, both domestically and globally. That interest is expected to escalate as increasing emphasis is placed on land stewardship and environmental protection in agroecosystems. The potential of agroforestry to simultaneously provide economic, environmental, conservation, and social benefits to agroecosystems is rapidly being recognized by federal and state agencies, universities, and conservation organizations. The need for and interest in agroforestry are national but specific needs and priorities vary by region and institution.
In spite of its potential, numerous barriers have impeded the development and application of agroforestry. The circumstances surrounding agroforestry are analogous to the challenges faced by urban forestry during its formative years -- it is unconventional, lacks recognition, and cuts across agencies and disciplines. Current agroforestry research and development (R&D), application, and extension activities are limited, unconnected, and minimally funded in relation to the need and interest. In response to these challenges, the community of interest for agroforestry has come together and is unified nationwide in support of the recommendations in this paper.
The needs are pervasive. Specifically, more emphasis is needed on technology development, systems integration, application and decision-support tools, technology transfer to agriculture and natural resource professionals, and technical assistance to landowners. A focused effort is needed to accelerate the development and application of agroforestry practices. The immediate need is to get agroforestry on the ground. This can best be achieved through a concerted effort to put into practice what is already known.
Improved technologies and information are only part of the challenge. A determined effort is needed to strengthen partnerships and cooperation among federal agencies, and form alliances among federal, state, university, and private sectors to develop, disseminate, and apply agroforestry technologies. There is a need to overcome barriers and build bridges. Agroforestry is an unprecedented opportunity for interagency cooperation. A coordinated/cooperative "Team USDA" approach is necessary to efficiently/effectively implement agroforestry. Closer linkages are required between ongoing agricultural systems and natural resources R&D and extension programs in order to be successful and effective.
The Needs and Opportunities for Agroforestry
Water and wind erosion, excess nutrient and pesticide movement, and a lack of biodiversity on farms and ranches continue as major deterrents to sustainable agriculture in the U.S. The National Resources Inventory (NRI-1982) identified 143 million acres of highly-erodible croplands that are now under conservation compliance plans which could be enhanced with agroforestry practices. Included in that figure are 112 million acres with an erodibility index (EI) greater than 8 - lands with an EI equal to or greater than 8 and planted to an annual crop must have conservation compliance plans in place by January 1, 1995. Failure to comply makes participants ineligible for USDA benefits.
Agroforestry can address these needs in two ways: (1) rehabilitation of degraded lands by conversion to alternative production agroforestry practices like alley cropping, tree/pasture systems, and fuelwood plantations; and (2) protection of sensitive lands by integration of windbreaks, riparian forest buffers, and other conservation agroforestry practices.
Of the 36.5 million acres enrolled in the Conservation Reserve Program (CRP), only 2.5 million acres (6. 8 %) are enrolled in tree planting options. Excluding the southeast, where most of the tree planting was for pulp production, tree planting under CRP was a disappointing 2 % . In the 12th signup, when a priority was placed on achieving water quality and wildlife benefits, the enrollment in tree planting options jumped to 11.4%. Thus, there is a clear relationship between tree planting and these desirable benefits. Moreover, trees have staying power. A 1991 Forest Service survey found that over 95 % of the trees planted under the Soil Bank Program are still at work today. In any extension of the CRP, more recognition and priority should be given to the long-term economic, conservation, and environmental benefits of agroforestry practices (e.g., windbreaks, filter strips, alley cropping, tree/pasture systems, tree/specialty crop systems, and wildlife habitat).
Agriculture is one of the major contributors of non-point source pollution in the US. According to the 1982 Soil Conservation Service's NRI, there are 737,000 miles of streambank nationally without woody riparian vegetation. The 1993 NRC report entitled "Soil and Water Quality: An Agenda for Agriculture", recommends greater use of "field and landscape buffer zones" in concert with improved farming systems to maintain soil and water quality. An agroforestry practice with enormous potential is multistrata (multispecies-tree/shrub/grass) riparian buffer strips. Buffer strips are capable of removing 80 % of the sediment, nitrogen and phosphoruscontaminants in surface runoff. Riparian buffer strips also yield wood products, hold water during peak flows, reduce bank cutting, and enhance aquatic environments and biodiversity.
Windbreaks are the most common and widespread agroforestry practice currently applied in the U.S. According to the Soil Conservation Service's NRI, the existing 175,000 miles of windbreaks are in a steady-state condition, but overall health and effectiveness are declining. Data from a 1992 SCS windbreak condition survey indicate that about 75 % of these windbreaks need renovation to maintain their function. A concerted effort is needed to restore or replace aging and declining windbreaks, and establish new ones.
Of the 405 million acres of rangeland and 131 million acres of pastureland, 58 and 48 million acres, respectively, are rated as having high or medium potential for conversion to cropland. If that occurs, the conversion should be to sustainable systems that include agroforestry practices. The need for riparian buffer strips is equally strong on western rangelands and central croplands. In open lands of the northern states there is an acute need for tree/shrub snowfences to control drifting snow, and tree/shrub livestock shelters to protect animals from severe storms. In the southeast and northwest, tree/pasture systems can increase forage and livestock production, protect livestock, and provide tree products.
A complex issue facing rural communities in America today is the decline in profitability of the small family farm. More than 50% of farm family income is often derived off the farm. Especially in the Northeast, Northwest, and Southeast, substantial areas of cropland are reverting to forest cover. Through the intensive management of these lands, new industries are emerging based on alternative agroforestry systems that grow high-value understory crops (e.g., foliage plants, mushrooms, and ginseng) under the protection of forest cover. These forest/specialty crop systems can substantially increase the value of these lands and contribute to the economic revitalization of rural areas.
Urban expansion is continually encroaching on agricultural lands. Conflicts are particularly acute in the urban/rural interface. Agroforestry can effectively address problems like stormwater runoff and sedimentation, wastewater and sludge disposal, and control of noise, wind, dust, and snow. Increased emphasis is needed on these non-traditional applications of agroforestry as a part of the Urban Resources Initiative.
A pervasive barrier to agroforestry acceptance is a lack of information on the tangible and intangible benefits to the farmer, the environment, and the public. Like any other conservation/land-use practice, agroforestry must be justified in terms of costs and benefits. Three economic issues that need to be addressed for the benefit of the farmer are: (1) the up-front fixed costs from installing a multi-crop (tree/crop/livestock) production system; (2) the initial time period required to realize income from land devoted to tree and other crop production; and (3) the amount of income to be realized and the value of diversification of income sources. It is a simple case of developing and providing the needed information. From an operational standpoint, agroforestry increases flexibility in agricultural operations. Finally, agroforestry offers farmers economic options other than row crops.
Agroforestry provides opportunities for international exchange and cooperation. The issues that agroforestry addresses are quite similar domestically and internationally: soil depletion, land degradation, loss of biodiversity, economic diversification, pollution, and sustainable development. Interest in agroforestry is rapidly building because of its unique ability to simultaneously address these economic, environmental and social issues. Increased emphasis is needed within USDA's global mission to support the development and use of agroforestry.
Changing demands are being placed on agriculture. The issue is broadening to sustainable development in agroecosystems. The public's expectations are for agriculture to continue to be productive and profitable, provide adequate quantities of safe food, yet be in harmony with the environment. In the future, farm support programs will likely focus more on the infrastructure of the agroecosystem than on the actual crop.
In response to these trends, USDA agencies are committed to developing an ecosystem-based approach for planning and implementing programs at farm, watershed and landscape scales. Since agroforestry is a part of the infrastructure of sustainable agricultural land-use systems, foresters, wildlife biologists, agronomists, etc., need to participate in teams approaching the concept of sustainable development in agroecosystems. Ecosystem management is a process, not a product. Thus, it is paramount that multi-agency and multi-disciplinary teams be utilized to develop an ecosystem-based approach to planning and to provide assistance on private lands.
As natural resource management advances toward an ecosystem-based approach at a watershed scale, it becomes obvious that trees are an important part of the agroecosystem infrastructure. Trees in agroforestry practices are needed to provide long-term protection of soil and water quality, enhance the resilience of the system, improve wildlife habitat, contribute to the maintenance of biodiversity, and help provide for people's physical and economic vitality. The agroforestry component of the system is the single most important source of biodiversity and is essential for healthy ecosystems.
To develop an ecosystem-based approach, multi-agency and multi-disciplinary pilot projects are needed in priority watersheds to blend and balance technologies and expertise to optimize integrated production/conservation systems. These projects should have a strong emphasis on understanding the economic, environmental, and social interactions between agricultural systems and natural resources. The outputs should be: (1) a better understanding of ecosystem component interactions; (2) identification of alternative scenarios; (3) evaluation of the economic, environmental, and social consequences of each scenario; and (4) decision-support models/tools based on this information.
Establish an Agroforestry Subtitle in the 1995 Farm Bill to address agroforestry's unique opportunities, needs and challenges. The circumstances surrounding agroforestry are analogous to those confronting urban forestry in its formative years. Focused policies and programs are needed to obtain recognition and acceptance, and effectively accelerate the development and implementation of agroforestry.
Establish a USDA Interagency Coordinating Committee and National Coordinator for Agroforestry to: (1) build understanding, acceptance, and support for agroforestry across agencies; (2) coordinate existing and new programs; and (3) identify needs, priorities, and direction. Federal agencies need to cooperate and provide national leadership for agroforestry. Membership should include the Forest Service, Soil Conservation Service, Agricultural Research Service, Extension Service, Cooperative State Research Service and the Agricultural Stabilization and Conservation Service. A national coordinator is needed to strengthen alliances across agencies and sectors, and NGO's. Better coordination and cooperation would increase overall efficiency and effectiveness and help achieve the goals of the National Performance Review. The associated costs would be offset by savings from increased efficiency. This option is recommended for immediate action using existing authorities.
Establish Regional Agroforestry Organizations to enhance linkages and information exchange among agroforestry practitioners, researchers, technology transfer specialists, and extension specialists throughout each region. Each regional organization should identify and recommend agroforestry development needs and priorities, and assemble task forces to evaluate emerging issues. There should be close linkages among the regional organizations, the National Agroforestry Coordinator, and the USDA Interagency Coordinating Committee. The cost of the regional organizations would be offset by savings from increased efficiency and effectiveness. It is recommended that the Association for Temperate Agroforestry (AFTA) take the lead in establishing regional organizations. No new authorities or action by USDA would be required to implement this option.
Establish a National Agroforestry Advisory Council to: (1) develop understanding, acceptance, and support for agroforestry; (2) identify national and regional needs; (3) identify research technology transfer, and training needs; and (4) recommend policies and programs required to ensure that future needs are adequately and efficiently met. Membership should include representatives of federal agencies, state agencies, institutions, and grassroots NGO's. The associated costs would be offset by increased efficiency in meeting USDA goals. The advisory council can be established with existing authorities, but a new statutory authority in the agroforestry subtitle that includes an exemption from the Federal Advisory Committee Act (FACA) is recommended.
Establish a National Interagency Agroforestry Center and Clearinghouse for Agroforestry Cooperation. The existing Center for Semiarid Agroforestry/National Clearinghouse for Agroforestry Cooperation and Promotion was authorized in The Food, Agriculture, Conservation and Trade Act of 1990 (FACTA-Title XIIState and Private Forestry, Ch 2, Sec. 1243). It is recommended that the semiarid focus be dropped and adequate resources provided to meet the national needs for agroforestry. An interagency joint-venture is imperative to enhance partnerships, cooperation, efficiency, effectiveness, and accomplishment of goals. To be effective, the Clearinghouse should facilitate and cost-share demonstrations, applications, syntheses, assessments, development of tools, and training workshops. The cost to fully implement the Center/Clearinghouse is $5 million/year. An amendment of the existing authorization would be needed to make these desired changes.
Provide Focused Funding for Agroforestry Research, Development, Applications, Demonstrations, Technology Transfer, and Training. An agroforestry competitive research grants program through the National Research Initiative Competitive Grants Program is required. A provision for focused funding for agroforestry research and development through appropriate USDA agencies, including Forest Service, Agricultural Research Service, Cooperative State Research Service, and the Economic Research Service will also be required. To attain the immediate need of putting what we know into practice, enhance agroforestry technical assistance by providing funding to the Soil Conservation Service, Extension Service and State Forestry Agencies to re-train professionals, hire new expertise, and establish watershed-level demonstration projects. Funding should be tied to cooperative/partnership and system-based efforts. The USDA Interagency Coordinating Committee, National Advisory Council, and the National Clearinghouse should play advisory/facilitative/coordination roles in the overall effort. Focused funding would result in an accelerated effort to develop and apply agroforestry technologies, information, and tools. Recommended funding is $25 million/yr. Specific language and authorities would be needed to establish focused programs.
Increase Emphasis on Field and Landscape Buffer Zones. In accordance with the NRC recommendation, more emphasis should be placed on the creation of field and landscape buffer zones that utilize agroforestry practices to protect soil and water quality, in concert with efforts to improve farming practices. This is an opportune area in which to develop, integrate, and evaluate appropriate technologies, and is a good example of how increased funding should be tied to cooperative/partnership efforts. Technical and financial assistance should be targeted to selected states for ecosystem-based pilot projects in high priority watersheds to demonstrate riparian forest buffers, windbreaks, alley cropping, tree/pasture systems, forest farming and other agroforestry practices. Funding to implement this recommendation should be provided in the other options previously discussed, the Sustainable Agricultural Research and Extension program (SARE), the Water Quality Incentives Project (WQIP) and other programs focused on water quality. New authorities would not be needed, but specific language is desirable to strengthen the emphasis on agroforestry and the tie between funding and cooperative/multidisciplinary efforts.
Increase Emphasis on International Agroforestry Technology Exchange. Agroforestry is an outstanding opportunity for USDA, within its global mission, to encourage the development and use of sustainable systems as an alternative to destructive agricultural systems. Furthermore, agroforestry is an area where the U.S. can benefit greatly from cooperation and technology exchange with other countries that have more extensive experience. The enhanced effort should be implemented through coordination between the International Forestry branch of FS, and the International Conservation Division of the SCS, and should be linked to the Interagency Center for Agroforestry/National Clearinghouse to facilitate interagency, university, and NGO participation. The cost associated with this option is approximately $1 million/yr. Specific language in the Global Climate Change Prevention Act (Secs. 2402-2407) is recommended to establish the increased priority for agroforestry international exchange, provide for funding needs, and provide direction.
Terry Johnson USDA-SCS
Boyd Post USDA/CSRS/NRF/SS
Arthur W. Allen USDI-National Biological Survey
Fred Deneke USDA-FS, S&PF
Bill Farris (representing NASF)
Bruce Wight USDA-SCS
Gene Garrett (representing NAPFSC)
Jack Slusher (representing USDA-ES)
Michael A. Gold (President, AFTA)
Deborah Hill (representing AFTA)
Louise Buck (representing AFTA)
John Rosenow National Arbor Day Foundation
Henry Pearson USDA-ARS
Mike Majeski USDA-FS
Gary Hergenrader (representing CWSF)
Bill Rietveld USDA-FS
Jerry Bratton USDA-FS
Kerry Herndon EPA - Region VII
Dick Schultz (representing AFTA)
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| Executive Summary | Agroforestry Concept | Rural Economic Development |
| Field & Landscape Buffers | Land Retirement Programs | Integrated Production Systems |
| Rural-Urban Interface | Policy Actions |
Introduction by Mike Gold, AFTA President
Sustainable development in agricultural ecosystems has emerged as one of the most complex and critical issues facing the nation today. How do we deal with the many negative environmental impacts of agriculture, maintain productivity, and provide for people's needs? There are many stakeholders involved, and we need to do it cost effectively to meet the needs of as many stakeholders as possible.
AGROFORESTRY - the blending of agriculture and forestry production and conservation practices - helps to provide answers. As an alternative to conventional agriculture, agroforestry is unique because it simultaneously addresses critical economic, environmental, and social needs within agroecosystems.
The Association for Temperate Agroforestry (AFTA) has teamed up with several other organizations and interest groups to develop the attached policy paper and individual issue papers on agroforestry in relation to the sustainable development needs in agricultural ecosystems.
In reading policy papers from other organizations, we recognize that there is much common ground. For example, we are all looking for long-term and multiple benefits from public investments in incentive programs. We look forward to working in collaboration with you and your organization to attain those goals through the application of appropriate technologies.
Agroforestry Policy Statement -- Executive SummaryAGROFORESTRY: BLENDING AGRICULTURE AND FORESTRY PRODUCTION
AND CONSERVATION PRACTICES
Agroforestry Defined:
Agroforestry is the intentional blending of agriculture and forestry production and conservation practices. Such integrated systems bridge production agriculture and natural resource conservation with environmental protection and human needs.
Agroforestry practices include riparian buffer systems, streambank bioengineering, tree/pasture systems, tree/specialty crop systems, windbreaks and shelterbelts, wildlife habitat, living terraces, alley cropping, and forest farming.
Benefits of Agroforestry:
Benefits are increased crop production, alternative crops and diversified local economies, improved water quality, soil erosion and sediment control, filtering and biodegrading excess nutrients and pesticides, reduced flood damage, microclimate moderation, and diversified habitats for wildlife and humans. Key outcomes include:
National Needs Addressed Through Agroforestry:
1) Rural Economic Development.
Agroforestry practices should be used to develop new economic enterprises to supplement and diversify farm incomes and enhance local economies.
2) Field and Landscape Buffer Zones.
Agroforestry buffer zones should be used to maintain water quality, limit flood damage, enhance biodiversity, provide wildlife corridors, and enhance aesthetic values at field, watershed, and landscape scales. A concerted effort is needed to restore or replace aging and declining windbreaks.
3) Land Retirement Programs.
More emphasis should be placed on agroforestry practices to attain multiple and long term benefits in Conservation Compliance, Conservation Reserve Program, Wetlands Reserve Program, and the Clean Water Act.
4) Integrated Production Systems
More emphasis should be placed on integrated tree/crop/livestock farming systems to optimize economic production and environmental protection.
5) Resolving:Rural/Urban Interface Conflicts
Agroforestry technologies should be used to address rural/urban land use conflicts and the problems stemming from both urbanization and farming practices. Problems addressed include: stormwater runoff; lack of greenspace; streambank erosion and sedimentation; municipal wastewater and sludge disposal; confined livestock waste; and control of wind, noise, odors, dust and snow.
Policy Actions Needed:
1) USDA Leadership and Coordination.
The Secretary of Agriculture should provide national leadership to catalyze cooperation, synergy, and partnerships among federal, state, and private interests to advance the science and practice of agroforestry.
2) Research and Development.
To achieve the potential of the emerging science and practice of agroforestry, emphasis must be placed on interdisciplinary technology development and applications through a needs-driven program of basic and applied research.
3) Technology Transfer and Application.
A focused technology transfer effort is required to develop understanding, acceptance, and broader use of agroforestry technologies. Application of appropriate technologies needs to be supported by analyses of alternative land-uses in relation to markets and landowner acceptance.
4) Technical Assistance and Landowner Incentives.
More emphasis is needed on interdisciplinary watershed-level diagnosis, planning, and program delivery to achieve natural resource conservation. Technical assistance and incentives should be targeted to attain cost-effective watershed-scale goals. Technical assistance providers need to be trained in new and integrated conservation technologies.
Agroforestry is the intentional blending of agriculture and forestry production and conservation practices, to attain more diversified and sustainable systems. Agroforestry practices contribute substantially to generating the ecosystem diversity, ecological processes, resilience, and buffer zones important for long-term sustainability. It is more than simply a collection of tree planting practices. Agroforestry bridges production agriculture and natural resource conservation with environmental enhancement and human needs. .
Practices include riparian buffers, streambank bioengineering, alley cropping, living terraces, windbreaks, tree/pasture systems, tree/specialty crop systems, and forest/specialty crop systems (forest farming).
Benefits are increased crop production, alternative crops and diversified rural economies, improved water quality, soil erosion and sediment control, filtering and biodegrading excess nutrients and pesticides, reduced flood damage, microclimate moderation, and diversified habitats for wildlife and humans.
Outcomes include diverse, resilient, and sustainable farm enterprises and rural communities; and viable alternatives to more onerous and costly regulatory approaches to address societal environmental concerns such as soil erosion, water quality, and biodiversity.
Key Principles in Agroforestry:
Agroforestry systems provide lasting economic, environmental, and social benefits. At farm, watershed, and landscape scales, integration of agroforestry practices can transform our agricultural lands into stable, resilient, diverse, aesthetic, and sustainable land-use systems.
Agroforestry practices .integrated into existing agricultural land-use systems provide multiple crops and services to supplement and diversify farm income.
Examples of products from managed tree/crop systems include lumber and veneer logs, fuelwood, nursery stock, Christmas trees, nuts, fruits, and foliage. Specialty crops grown with the microclimate protection of trees include herbs, flowers, fruits, and vegetables. Forest farming specialty crops include ginseng, mushrooms, and foliage.
Agroforestry adds economic diversity to an agricultural system. It provides a landowner with the opportunity to develop a portfolio of short- and long-term investments to spread economic risk through diversification. For portions of farms that are unsuitable for annual crop production, woodlots and strip plantings provide an alternative productive land use. For example, wooded riparian corridors and "timberbelts" can produce sawlogs, wildlife, and recreational opportunities, while ensuring resource conservation.
Recent sharp increases in prices paid for trees from private lands has heightened interest in forest stewardship. But many landowners are unsure how to capitalize on the potential for generating income from trees. Agroforestry provides a way to plan for the future while meeting the needs of the present. By integrating agroforestry practices into the farming system, trees meet multiple economic, conservation, and social needs. The design and level of management must be tailored to meet each landowner's objectives.
Policy Actions Needed:
1) Establish sustainable economic uses of CRP lands, e.g., hay and grazing enterprises, high-value tree crops, tree products (nuts, foliage, etc), Christmas trees, woodlands, biomass, and tourism/recreation enterprises. Conversion should require a management plan and managed harvesting. Allow a 10-year contract extension if existing cover on CRP lands is converted to alternative managed economic use. Provide additional cost-share for tree planting on existing high priority CRP lands, in combination with contract extensions or easements.
2) Focus Small Business Administration grants to develop landowner enterprises and local/regional markets based on agroforestry systems that provide alternative sources of farm income. SBA support should be linked to technical assistance and cost-share programs delivered by other agencies.
The 1993 NRC report entitled: "Soil and Water Quality: An Agenda for Agriculture" recommends greater use of buffer zones. Agroforestry systems are the most appropriate means to attain the desired buffer zones.
Buffer zones should be part of the infrastructure of agricultural production systems. Their functions are to: (1) provide protection from environmental extremes; (2) reduce storm water runoff, (3) trap, filter, break down, and consume sediments and excess nutrients, fertilizers, pesticides, and animal wastes in runoff water; (4) enhance landscape- and bio-diversity, and (5) provide numerous environmental and social benefits.
Examples include windbreaks, shelterbelts, riparian buffer systems, living snowfences, contour hedgerows, and wildlife habitat plantings.
A Win-Win Situation
Agriculture-derived contaminants are the Nation's number one source of water quality impairment. Producers talk of being proactive in order to avoid regulation, but they need to act. The public needs to share the responsibility and cost. Establishing buffer zones are a way to work together to create a safety net, used in combination with judicious application of farm chemicals and fertilizers, to minimize the impacts of agricultural nonpoint source pollution.
Riparian Buffer Strips are Urgently Needed
There are 737,000 miles of streambank nationally without woody riparian vegetation. These aquatic environments are unprotected from adjacent land uses. Alternatively, riparian buffer strips are capable of removing 80% of the sediment and chemical contaminants in surface and shallow groundwater. Buffer strips also hold water during peak flows, reduce bank cutting, and enhance aquatic environments.
Windbreak Establishment and Renovation are Needed
The existing 175,000 miles of windbreaks are at a steady-state level, but 75% need renovation to maintain their health and function. A concerted effort is needed to restore or replace aging and declining windbreaks and establish new ones. The beneficial effects of windbreaks on soil retention and crop yields are well documented in over 80 studies.
Management is Needed
Trees are an effective sequestering system to remove excess nutrients and carbon dioxide and store them on-site in the form of wood. Partial tree harvesting in buffer zones is necessary to clean the "biofilter", remove valuable products, and maintain their long-term effectiveness.
More emphasis should be placed on multiple and long-term benefits in the Conservation Reserve Program, Wetlands Reserve Program, and other land retirement and conservation programs. In CRP, most of the enrolled lands are planted to grass cover that can easily be plowed, whereas in the Soil Bank Program 80% of the trees planted are still at work today. Trees have staying power and provide multiple benefits.
Policy Actions Needed in CRP:
1) Seek contracts that optimize a mix of conservation benefits, e.g., soil erosion, water quality, and wildlife benefits. Bids should continue to be ranked through the use of an Environmental Benefits Index (EBI), as initiated after the 1990 Farm Bill.
2) More focus is needed on partial field conservation practices and other practices in priority areas with high environmental pay-offs, including riparian buffer systems streambank bioengineering, windbreaks, living terraces (contour hedgerows), wellhead protection zones, and wildlife habitat.
3) Convert CRP to a long-term protection program by using long-term easements to protect only the most environmentally sensitive agricultural lands. The cost-benefits are low for continuing enrollment of lands in Land Capability Classes I-III (about 60% of the current enrollment). These productive lands should be allowed to be returned to cropping under Conservation Compliance.
4) Special consideration should be given to enrollment offers that incorporate multiple resource protection objectives, cooperative bids submitted by landowners with adjoining parcels, and practices that increase the effectiveness of other conservation practices. Joint bids linking across farms provide opportunities for enhanced environmental benefits at the watershed and landscape levels, for example, extending riparian buffer strips along a greater number of stream or lakeshore miles.
5) Establish sustainable economic uses of CRP lands, e.g., hay and grazing enterprises, high-value tree crops, tree products (nuts, foliage, etc), Christmas trees, woodlands, biomass, and tourism/recreation enterprises. Conversion should require a management plan and managed harvesting. Allow a 10-year contract extension if existing cover on CRP lands is converted to alternative managed economic use. Provide additional cost-share for tree planting on existing high priority CRP lands, in combination with contract extensions or easements.
6) Allow CRP land to be used as set-aside acres.
More emphasis should be placed on integrated tree/crop/livestock farming systems that optimize economic production and environmental protection. Integrating tree, crop, and livestock production provides a means to expand and optimize farm products and income, while at the same time establish more sustainable systems.
Examples include silvopastoral systems, livestock windbreaks, living fences, livestock havens, buffer systems for confined livestock, alley cropping, tree/specialty crop systems, and forest/specialty crop systems.
Benefits accrue to animals, crops, ecosystems, and farmer income. Examples include livestock protection from environmental extremes, increased forage production, lower feed costs, increased survival of newborns, increased milk and wool production, alternative high-value crops, diversified income, buffering of pollutants in runoff water, and more sustainable production systems.
Tree/Livestock Systems
Silvopastoral systems (scattered trees in pastures) increase forage and animal production. Living fences separate pastures and provide both animal protection and tree products. Livestock windbreaks protect confined livestock in the farmstead, reducing feed costs. Clusters of trees in open ranges provide shelter from environmental extremes, especially during spring calving. Tree/shrub/grass buffer systems located between confined livestock operations and surface water help maintain water quality and convert excess nutrients into valuable tree products.
Tree/Crop Systems
Alley cropping is strips of trees or shrubs with crops grown in the alleys between the strips. Agricultural crops grown between tree/shrub rows provides annual income from the land during the early years while the longer-term nut or wood crop is establishing itself. In tree/specialty crop systems, the microclimate protection of trees enables the production of sensitive high-value crops in arduous environments, for example windbreak systems protecting herbs, fruits, vegetables, nursery stock, or flowers.
Forest/Crop Systems
Forest farming is managed systems where a high-value crop is grown under an existing forest overstory. Examples include ginseng, shiitake mushrooms, and certain foliage plants. These systems are distinguished from forest products in that the systems are intentionally established and intensively managed.
Agroforestry technologies should be utilized to address rural/urban land-use conflicts and the problems stemming from both urbanization and farming practices. Problems addressed include: stormwater runoff; lack of greenspace; streambank erosion and sedimentation; municipal wastewater and sludge disposal; confined livestock waste; and control of wind, noise, odors, dust, and snow.
Appropriate technologies include streambank bioengineering, riparian buffer systems, living terraces, windbreaks to protect fields and screen confined livestock, living snowfences, tree/specialty crop systems, and wildlife habitat enhancement.
A Win-Win Situation
Land-use conflicts are particularly acute at the rural/urban interface, and problems are shared by both rural and urban populations. Soil and Water Conservation Districts and State Conservation Agencies need to be more responsive to divergent rural/urban priorities. Agroforestry technologies can resolve the environmental conflicts between rural and urban land-uses, and at the same time establish stable, diverse, and aesthetic systems. Opportunities exist to establish new tree/specialty crop enterprises adjacent to urban markets. Tree planting in interface zones and urban watersheds provides an excellent opportunity to involve volunteer groups from both rural and urban areas to work together to achieve environmental protection goals.
More Bio-Engineering is Needed
Treatment strategies need to go beyond constructed structures, such as channelization and floodwater impoundments. Integrating agroforestry technologies into farms, watersheds, and landscapes establishes a "green infrastructure" that protects system components, buffers environmental impacts, and retards stormwater runoff. Examples include streambank bioengineering as an alternative to rock gabions, multiple farm ponds and wildlife habitat plantings as an alternative to flood control dams, and windbreaks and riparian buffer strips as an alternative to channelization. Vegetative approaches enhance water infiltration and retard runoff, rather than speed its disposal.
Take Land Stewardship to the People
Nearly 70% of the U.S. population lives in our cities and communities. Thus, the rural/urban interface is an ideal high-visibility location to demonstrate agroforestry technologies, and involve rural and urban stakeholders in the process. Such a focus will help build understanding and acceptance of the complexities of land stewardship in agricultural regions and develop stronger working relationships.
Partnerships! Partnerships! Partnerships!
Agroforestry is a hybrid, applied science and practice. Much emphasis is needed on building interdisciplinary teamwork, interagency partnerships, stakeholder participation in planning and delivery, and an ecosystem-based approach at farm, watershed, and landscape scales.
USDA Leadership is Needed
Cross-agency and cross-disciplinary cooperation needs to be catalyzed to effectively develop and apply agroforestry. Federal agencies need to cooperate and provide national leadership. Specifically:
1) Establish an Interagency Coordinating Committee for Agroforestry to: (a) build understanding and support for agroforestry across agencies; (b) coordinate existing and new programs; and (c) identify needs, priorities and direction.
2) Expand the National Agroforestry Center (FACTA Section 1243) to an interagency joint
venture. The Center must work interactively with the existing national network of cooperators to catalyze. partnerships, cooperation, and synergy.
Research and Development
In order to achieve the full potential of agroforestry, emphasis needs to be placed on needs-driven technology development. Decisions to implement costly incentive programs must be based on sound scientific information. Technology needs include improved practices and plant materials, quantifying the benefits of agroforestry, developing integrated production/ conservation systems, developing information integration systems to support ecosystem-based/watershed scale planning and program delivery, and socio-economic analyses.
Technology Transfer and Applications
Focused programs are needed to support the development and application of appropriate conservation technologies to meet the needs of multiple stakeholders. Programs should be needsdriven, competitive, and should encourage multidisciplinary teamwork that results in integration of technologies, involvement of stakeholders, and leveraging of funding through partnerships.
Technical Assistance and Landowner Incentives
More emphasis is needed on watershed-level diagnosis, planning, and program delivery to achieve natural resource conservation. Technology assistance and cost-share programs should be targeted to attain the most cost-effective watershed-scale goals, rather than be approached on a first come/first served basis.
User Rating: 4 / 5
A COMPREHENSIVE ASSESSMENT OF U.S. AGROFORESTRY (LONG VERSION)
The Agroforestry Component of the Resource Conservation Act Appraisal for the SCS
Prepared for USDA SCS (Account 68-3A75-3-134)
February, 1994
Submitted by Committee Chair: H.E. 'Gene' Garrett , University of Missouri
Committee Members: W.B. Kurtz, University of Missouri; L.E. Buck, Cornell University; J.P. Lassoie, Cornell University; M.A. Gold, Michigan State University; H.A. Pearson, USDA ARS; L.H. Hardesty, Washington State University; J.P. Slusher, University of Missouri
TABLE OF CONTENTS
AGROFORESTRY DEFINED
Examples of practices
POTENTIAL ACREAGE FOR AGROFORESTRY
ECOLOGICAL BENEFITS
Protection Benefits
Crop protection
Snow capture
Wind damage
Microclimate modification
Livestock protection
Tree/groundcover interactions
Faunal diversity/crop yields
Plant/insect interactions
Environmental Benefits
Water quality
Nutrient reduction
Biomass removal/saturation in woody VBS
Sediment reduction and stream bank protection
Impacts on fish populations
Herbicide and pesticide reduction
Air quality
ECONOMIC BENEFITS
Production Economic Benefits
Trees and crops
Grazing/haying natural pine
Protection Economic Benefits
Soil erosion control
Shelterbelts
Federal Agroforestry Programs
Conservation Reserve Program (CRP)
Center for Semi-arid Agroforestry (CSA)
South Central Family Farm Research Center
Related Federal Technical Assistance and Cost-Share Programs
Stewardship Incentive Program (SIP)
Forestry Incentives Program (FIP)
Agricultural Conservation Program (ACP)
Environmental Easement Program (EEP)
Tree Planting Initiative
Sustainable Agriculture Research
Government Price Supports and Taxes
Agroforestry Research Extension and Education at Land Grant Universities
State Agroforestry and Related Programs
Association for Temperate Agroforestry (AFTA)
Non-profit membership groups
Summary of Policy Relating to Landowner Incentives
ACHIEVING AGROFORESTRY'S POTENTIAL
SUMMARY OF AGROFORESTRY DEVELOPMENT NEEDS
LIST OF TABLES (Note: All tables are in a separate 221 KB PDF file. Click here to view).
Table 1. Cropland Acres1 (1,000's) With an Erodibility Index (EI)2 <_ or > 8 on Nonfederal Rural Land
Table 2. Total Nonfederal Pasture and Rangeland Acres' (1,000's) and Acres With High and Medium Potential for Conversion to Cropland or Agroforestry (Based upon the 1982 NRI)
Table 3. Total Nonfederal Forestland Acres' (1,000's) and Acres with High and Medium
Potential for Production of Specialty Products (Based upon 1982 NRI)
Table 4. Orchard (fruit and nut) and other Horticultural (vineyard, bush fruit
and berry) Acres' (1,000's) on Nonfederal Rural Land
Table 5. Lineal' Miles2 Of Riparian Area' Streambank Vegetated With Shrubs
Table 6. Lineal' Miles of Riparian Area' Streambank Without Trees or Shrubs
Table 7. Percent of Land in the 18 Western States in Federal Ownership
Table 8. Summary of Minimum Woody Corridor Planting Needs in the United States1 (in 1,000's)
"A farm can be regarded as a food factory and the criterion for its success is saleable products. Or, it can be regarded as a place to live, and the criterion for its success is harmonious balance between plants, animals and people; between the domestic and the wild; and between utility and beauty." - Aldo Leopold
Never in history has global concern for the consequences of human land use been more widely shared. Many regions of the world cannot meet their growing populations most basic needs for food, water and energy. Soil erosion adds to food, energy and transportation costs and threatens future food production capacity. Nonpoint source pollution from forest and agricultural lands restricts access to safe water. Loss of vegetation from land development and site degradation affects our aesthetic environment, global climate patterns and the quality of the air we breathe. Such problems are often the legacy of our success in maximizing production of one or more agricultural products in a financially optimal fashion without sufficient knowledge of, or regard for, impacts on future productivity and the environment. This was a rational economic choice when long-term consequences were unknown, when resources appeared to be relatively unlimited, and when technology promised means for further intensifying production. Now that we are discovering undesirable longer term consequences of current land-use systems, alternatives must be sought. one alternative is to model managed ecosystems after the structure and functions of naturally-occurring ones by reestablishing complexity in time, space and biodiversity. This would lead to a shift away from separating land uses on discrete parcels to integrating them on a landscape level. Agroforestry, which exploits the interactions between trees and crops (including livestock) when they are grown together, bridges the gap between production agriculture and natural resource management. This provides opportunities to integrate land uses on a landscape level. Furthermore, properly designed agroforestry systems provide environmentally and economically sound alternatives to unsustainable production systems.
In the past, progressive land management in North America meant increasingly intensive use of a site for production of a single product -- corn, rice, wood, or others, -- in which other values such as watershed and wildlife habitat were competitive, or at best, secondary. In contrast, agroforestry seeks to optimize production of multiple products and benefits by manipulating the interactions between components. For example, sheep grazing a forest plantation provide short-term revenue and reduce competition. Trees planted on a floodplain yield wood products, trap sediments during peak flows, reduce bank cutting and protect adjacent croplands and downstream water quality. Resource conservation and production goals are integrated rather than assumed to be tradeoffs. Several decades of development of agroforestry systems and their application in temperate nations such as New Zealand and China demonstrate the range of conditions under which this approach has been successful. Agroforestry requires shifting our thinking in both spatial and temporal domains, and demands skills in managing, rather than reducing complexity. Traditional disciplinary approaches to problem-solving such as the forester dealing with the trees, the soil scientist with the soil, and the hydrologist with the water, are no longer sufficient. This may be one reason why less developed nations that have never strictly segregated land uses are today's world leaders in development and application of agroforestry technologies. Agroforestry challenges land managers to transcend disciplinary boundaries and explore the potential synergism between production agriculture and natural resource management. Essential to this is an understanding of hierarchical scalar relationships within ecosystems and recognition that defined ecosystem "boundaries" exist primarily for managerial convenience.
Scientific exploration of complex, long-lived systems is difficult when only technique constrains the enterprise. Such exploration is nearly impossible when institutional and fiscal constraints also apply. Hence, the scientific basis for agroforestry lags behind the emerging need for its application as an alternative land use strategy in the United States. This gap is further exaggerated by the large clientele served. The farmer needs an immediate economic return; the consumer safe and affordable food; the parent, assurance of a safe future environment; and the general citizen, hope for global and interspecies equity. All are measured in different currencies and on different time scales. A forester may not be prepared to consider a tree as an individual landscape component. The farmer may see windbreaks as a loss of productive acres. The economist may not be able to value reduced soil erosion and so forth. The requirements of implementing complex systems over a range of environmental and social conditions are daunting.
Both the development and application of agroforestry has proceeded rapidly in many developing nations in the tropics. The problems confronting individuals and institutions were sufficiently urgent to justify bold approaches beyond the safe confines of scientifically defined management systems. While adoption has been slower in the temperate regions of the world, two decades of observational data and applied research suggest that agroforestry should be vigorously explored as a possible component of improved land-use strategies in the United States. Current interest in ecosystem management strongly suggests that we should embrace the complexity inherent to agroforestry and apply agroforestry principles, where appropriate, to better meet our current and future needs for the products and services of the land.
Agroforestry is an intensive land-management system that optimizes the benefits from the biological interactions created when trees and/or shrubs are deliberately combined with crops sad/or livestock.
Four key components of this definition are: (1) land use is intensive; (2) benefits are optimized; (3) biological interactions are increased; and (4) trees and/or shrubs are deliberately combined with crops and/or livestock.
Intensive land use--Agroforestry utilizes management practices for producing trees with crops and/or livestock. Management schemes incorporate intensive practices such as tree planting, annual cultivation, fertilization, irrigation, weed control, liming, grazing or combinations of these and other practices. Therefore, agroforestry manipulates the agroecosystem to achieve optimal benefits. Grazed forests or woodlands extensively managed as natural ecosystems also produce wood products and forage for livestock or wildlife but without using intensive approaches such as annual inputs of nutrients, herbicides, or mechanical treatments. These latter systems are often excluded from the agroforestry classification but, because of similar interactions between woody plants, forage supplies and livestock, they are considered a subset of the agroforestry land-use classification for management purposes.
Optimizes benefits--As a land-use system, agroforestry provides many benefits for humankind. These benefits may be economic, environmental, biological, or social. Optimization implies that the various factors can be combined, through compromise, to best serve the interests of the user and society. Since each user may have different objectives -- soil conservation, minimization of inputs, integrated pest management, greater profit, aesthetics -- optimization of system components will vary.
Biological interactions--Protective and productive benefits are realized from agroforestry practices. They are the products of biological interactions resulting from the proper mix of woody perennials, herbaceous species and livestock. These interactions affect soil, water and air quality, biological diversity, wildlife habitat, aesthetics, economics and, ultimately, rural community development. As an example, riparian filter strips may help reduce soil erosion from cropland and improve habitat for some particularly desired fish or wildlife species while enhancing visual landscapes.
Trees and/or shrubs deliberately combined with crops and/or livestock-An intentional combining of trees and/or shrubs with crops and/or livestock is an essential element of agroforestry systems. This aspect mimics the multispecies, multi-storied characteristic found in natural ecosystems while providing a variety of marketable commercial products. Crops may include conventional agronomic commodities such as corn, cotton and soybeans; specialty commodities such as ginseng, golden seal, shiitake mushrooms and honey; both warm- and cool-season tame pasture; and managed native forages -- forestland, woodland, pastureland and rangeland. Trees and shrubs may consist of high-value timber/veneer, nut/fruit producing woody perennials and others. Livestock are animals kept for use on the farm or raised for sale and profit.
Some prominent examples of agroforestry practices applicable to the U.S. temperate zone include: (1) riparian vegetative buffer strip (VBS) systems -- a combination of vegetative types established on stream and river banks -- to regulate microenvironments and protect fish habitats or for regulating nonpoint source waterway pollution; (2) tree-agronomic crop systems such as alley cropping or intercropping -- planting rows of trees at wide spacings and cropping the alleyways -- for increasing and/or diversifying farm incomes, abating soil erosion and nutrient loading, and protecting watersheds; (3) tree-animal systems -- silvopastoral or forest livestock grazing, the intensive management of forages grown with trees for pasture purposes -- which are especially prominent in the west and south leading to economic, wildlife habitat, fire protection, and forest management benefits; (4) windbreak systems (shelterbelts) of noted importance in the plains and western states for protecting and enhancing production of crops and animals and stabilizing microenvironments; and (5) natural forest/specialty crop systems -- forest farming, the development of suitable microenvironments in natural forest stands for growing specialty crops such as mushrooms and ginseng.
POTENTIAL ACREAGE FOR AGROFORESTRY
While few data exist which would allow a reliable estimation of the degree of current use of various agroforestry practices, vast acreages of forestland, pastureland, rangeland, cropland and stream corridor suitable for agroforestry occur throughout the United States (Tables 1 through 6). The adoption and application of practices varies by region and is driven by local tradition, economic factors and land-ownership patterns (government vs private).
Approximately 32% of the U.S. land area is in federal ownership but the percentage varies significantly by regions and even within regions by states. In the western states, where opportunities exist for agroforestry practices such as riparian buffer strips that affect water quality and wildlife habitat, and silvopastoral management of forest plantations in lieu of herbicide use, federal ownership ranges from 89.5% in Alaska and 81.7% in Nevada to a low of 6% in Colorado (Table 7). In contrast, in the northern plains -- Kansas, Nebraska, North Dakota and South Dakota -- federal ownership ranges from a low of 1.4% in Kansas and Nebraska to a high of only 6.4% in South Dakota. The prospects for application of agroforestry practices to federal lands are probably limited in the short-run by the long time frames committed to existing land-use plans. However, mounting pressure to resolve land-use issues such as anadromous fish habitat, forest health, threatened and endangered species and rural community stabilization is leading to a new openness toward nontraditional land-use decisions on federal land. In spite of this, in the short-term, the application of agroforestry principles primarily will be limited to the private sector.
The growing intensity of land-use practices, the increasing public interest in biological conservation and legislated requirements for resource impact assessments, all serve to encourage private landowners to evaluate the potential of agroforestry to meet their needs. Agroforestry systems could provide landowners with land-management options which have environmental benefits and provide sustainable economic gains. When land-management advisors were surveyed recently in Washington state, all of the respondents indicated that agroforestry could be useful in USDA-mandated conservation plans.1
The potential for agroforestry on highly erodible cropland is enormous. More than 112 million acres of non-federal cropland have an erodibility index (EI) of greater than 8 (Table 1). These lands could benefit greatly from the application of agroforestry practices, such as windbreak systems or alley cropping, designed for both production and protection.
In the Midwest, where considerable agroforestry research has been conducted, the five states of Missouri, Illinois, Indiana, Iowa and Ohio have more than 19 million acres of cropland with an EI greater than 10.2 Approximately 9 million of these acres are recommended for forestry plantings and would be ideally suited for agroforestry. In the plains states of Nebraska and Kansas, an additional 16 million acres of cropland are highly erodible (EI > 8) and would lend themselves well to windbreak or alley cropping systems (Table 1). Furthermore, within the United States there exists over 131 million acres of pastureland and another 405 million acres of rangeland (Table 2). Approximately 18 million of the pastureland acres are rated as having high potential for conversion to cropland and should, therefore, lend themselves to agroforestry. Another 40 million acres have medium potential for conversion. More than 8 and 40 million acres, respectively, of the rangeland also are rated as having high or medium potential for conversion to cropland and, we may assume, agroforestry.
Silvopastoral agroforestry has great potential in the United States but perhaps nowhere is it greater than in the pine belt of the south and in the west (Table 3). In the south, the pine and oak-pine forestland totals about 99 million acres. This land either produces or has the potential to produce significant forage. resources. Much of it could be successfully converted to silvopastoral management. In the Pacific region -- California, Oregon, Washington -- nearly 40 million acres of forest exist. Of this, approximately two million acres (Table 3) are rated as having good potential for conversion to cropland and could produce high-quality wood/forage under sound management practices. Millions of additional acres could be seeded to forages and, through intensive silvopastoral management, result in significant economic gains for the region without harming trees or environment. Forestland grazing, including plantation grazing, is the most common agroforestry-related practice in Washington state, and perhaps in the region.3 Moreover, recent reviews conclude that properly managed forest and plantation grazing can benefit tree growth. The impact of forest grazing on ecosystem processes is not fully understood at this time. However, it is generally believed that under conditions of intensive silvopastoral management, impacts are directly related to the intensity of grazing.
Forested areas also provide opportunities for the production of specialty crops which are sold for ornamental, culinary or medicinal uses. While silvopastoral management and the production of specialty crops may be incompatible, forest landowners not interested in livestock grazing may choose to develop enterprises such as the production of food items (mushrooms, sugar maple), medicinal plants (ginseng, golden seal) or even shade-tolerant ornamental plants which require the microenvironment of forested acreage. Specialty crops are already a multi-million dollar business in many parts of the United States -- northeast, lake states, Appalachia and the Pacific northwest. In Kentucky alone, ginseng production is a $5 million per year businees.4 Much of the forested acreage available in the United States would readily lend itself to a variety of enterprises relating to the production of specialty crops. Much of the acreage under orchard management (Table 4) could also be adapted to accommodate specialty crops under agroforestry management. Seven states -- Michigan, New York, Florida, Georgia, Texas, Washington and California -- each have more than 180,000 acres of orchards which might benefit from conversion to agroforestry.
An agroforestry practice of enormous potential and in need of immediate broadscale adoption is the riparian vegetative buffer strip (VBS). Properly designed VBS help control water quality, flow regime, physical habitat and energy inputs in streams while providing wood products. They reduce the effects of traditional farming on stream quality while creating suitable habitat for a variety of wildlife species including aquatic inhabitants. Of special concern are streambanks without adequate vegetative protection where only shrubs and/or grasses or forbs are found (Tables 5 and 6). Many streams found throughout the United States could be greatly improved through the establishment of proper vegetation along their edges. In the corn belt alone -- Illinois, Indiana, Iowa, Missouri and Ohio -- where agricultural chemicals are used extensively, more than 85,000 miles of stream and river banks are unprotected by trees or shrubs. An additional 80,000 miles are unprotected or have only minimal protection in the heavily farmed states of Kansas, Nebraska, North Dakota and South Dakota. California has more than 40,000 miles of unprotected stream and river banks.
The potential for agroforestry varies by regions, reflecting the diverse landscapes, values and regional/local economies. Agroforestry adoption emerges and changes as a function of complex socio-economic factors, combined with the innovative capacity of landowners to respond to respective market forces and social values. Notwithstanding these qualifications, it appears that the potential for agroforestry is vast, as is the acreage where it may be applied.
Properly designed agroforestry systems patterned after natural ecosystems yield many benefits. Such systems require active manipulation of vegetation diversity. Landscape diversification of crop-fields, through the establishment of windbreaks, shelterbelts, woody hedges, alley cropping systems, and others leads to:
ECOLOGICAL BENEFITS
Protection Benefits
When carefully designed, woody and herbaceous corridors such as hedgerows, windbreaks, shelterbelts, wooded alleys and forest edges, can be need to protect soil, conserve moisture and improve dryland crops. Corridors provide habitat that benefit wildlife within agricultural landscapes and provide diversity that supports natural enemies of crop pests. Benefits to wildlife include protection from wind and adverse weather, escape or refuge cover, food and foraging sites, reproductive habitat and travel areas.5 6
Negative effects of woody corridors upon crops include a reduction in available land for planting, the potential for increased wind turbulence, competition for soil moisture and nutrients, allelopathy and shading. All of these potentially negative effects occur in immediate proximity to the woody corridor. Most can be mitigated through proper species selection, corridor design and management (e.g., corridor root pruning).
Beneficial effects leading to increased crop yields are afforded by woody corridors. Increases are attributed to reduced wind erosion, improved microclimate, snow retention and reduced crop damage by high winds.7 Twenty year-old woody corridors in which trees and shrubs occupy only 6% of the land unit have been shown to provide adequate crop protection in Nebraska.8 Land protected from wind is, in general, more productive per unit area than unprotected land and total crop output increases. Reducing the number of acres required to achieve crop production goals reduces requirements for crop inputs including fossil fuels and fertilizer.
Snow capture -- where a significant amount of annual precipitation falls in the form of snow, entrapment and retention by woody corridors has been found to increase crop yields and provide a layer of insulation preventing winter kill of sensitive crops such as winter wheat.9
Wind damage -- Small-seeded, shallow-sown crops, and newly emerged crops are very susceptible to direct wind damage. Severe postemergent crop damage can also occur due to sandblast -- the effect of soil particles abrading plant tissue. The effects of sandblast injury varies from reduced yields and delayed maturity to mortality. Woody corridors trap wind-borne soil and reduce wind velocity, thereby reducing wind erosion and sandblast injury. Crop damage can also occur due to lodging. Shelterbelts have been found to reduce wind-induced lodging. In one case, lodging of oats was prevented to a distance of 10 h (height of trees) behind a single-row Douglas fir shelterbelt.8
The overall benefit of shelterbelts on crop yields, via reduced soil erosion, depends on the relationship between erosion and crop productivity. Commonly, only small annual reductions in productivity are found to be due to the loss of topsoil. The magnitude of these losses depends upon soil texture, root zone depth and soil regeneration rates as well as the amount of soil lost. For example, reports suggest that shelterbelts increase yields of small-grain cereals in low-yielding fields more than in high-yielding fields due to differences in soil texture and consequent moisture availability. 10
Microclimate modification -- This can influence all production components of an agroforestry system. Agronomic crops may differ significantly in their responsiveness to shelter and associated microclimate modifications. Sheltering, however, generally improves growing conditions due to higher soil moisture, humidity and night-time carbon dioxide levels as well as lower evaporation and night-time air temperatures. Of greatest importance is the moderation of extreme temperatures, resulting in lower respiration rates. Collectively, these modifications tend to improve crop yield and quality and accelerate maturity.11
Windbreaks are especially important for livestock in northern climates. Properly positioned trees and shrubs can provide much needed protection for pastures, feedlots and calving areas. Reducing wind speed lowers animal stress, improves animal health and increases feeding efficiency of livestock.12 Canadian researchers have demonstrated that cattle on winter range require an additional 20% increase in feed energy, above maintenance, to offset the direct effects of exposure to a combination of cold temperatures and wind. Adequate wind protection has been found to reduce the direct effects of cold by more than half.13 Similar findings have been reported for swine and dairy animals.14
Underplanting black walnut with legume or grass covers can effect positive changes in the phonology of walnut. Compared with clean cultivation, the maintenance of legume or grass covers in walnut plantations delays bud break 6 to 12 days, thereby decreasing possible frost damage. Underplanting walnut with winter annual legumes also has been found to accelerate the onset of dormancy.15 Furthermore, seeding of plantations with cool season legumes, even without chemical weed control, can accelerate tree establishment and growth.
Alnus spp., non-leguminous nitrogen fixers, are recognized as having the potential for use in agroforestry management systems similar to that of legumes in agriculture. The concept of "intercropping vigor", in which dry matter production of mixed cultures exceeds that of pure plantings has been reported.16 The major benefits derived from the use of woody nitrogen fixers include the realization of optimal biomass yields per unit of land area, a reduction or elimination of the need for applied nitrogen fertilizer, improvement in soil fertility and soil physical properties, suppression of soil pathogens, and improved growth of associated species in mixed cropping systems.
Mixtures of annuals and perennials result in better nutrient capture and tighter nutrient cycling. Extensive, deep root systems and associated mycorrhizal fungi enable woody plants to enrich soil by recycling leached or unavailable nutrients at rhizosphere depths beyond the reach of annual plants. In addition, the trapping, retaining and recycling of nutrients contained in rainfall is enhanced.
Long-rotation, mixed-cropping systems using nitrogen-fixing trees as nurse plants usually require that the nurse crop be harvested, poisoned, or removed before the final harvest of the timber crop. However, reported benefits may outweigh the inconvenience. Mixed plantings of nitrogen fixing autumn olive (Eleangus umbellata) with walnut stimulates walnut growth. After 10 years, walnut grown with autumn olive were 80% taller and 104% larger in diameter than those grown alone. In addition, the mixed plots were higher in soil nitrogen, lower in soil moisture, and had lower soil and air temperatures.17 Similar responses have been found using other species, suggesting an improvement in economic viability when intermediate quality sites planted with high-value tree species are interplanted with nitrogen fixers.
Diversity in habitat and fauna through the application of agroforestry principles appears to bring stability to agricultural landscapes. A recent review of shelterbelt literature indicates that at least 108 bird species and 28 mammalian species use shelterbelt habitats. Of the 108 bird species found within agricultural landscapes, 29 have been reported to benefit substantially from the microenvironments created. Similarly, research in the Midwest indicates the importance of grassed waterways, woody and herbaceous edges around crop fields, fencerow corridors and riparian areas to birds in agricultural landscapes.18 19
Of practical importance, birds as predators of insects may affect crop paste within the crop field, the edge habitat or the wooded corridor. Birds living in a wooded corridor forage in the crop field and consume insect pests blown or attracted to the edge. Calm winds on the leeward side of wooded corridors appear well suited for bird and bat insect predation. Downy woodpeckers have been found to be important predators of European corn borers in North Dakota, Louisiana and Arkansas. Woodpeckers consume the larvae by pecking into the corn stalks after harvest. Other studies have found bird predation on insect pests in tobacco and fruit orchards. Although it is unlikely that birds or other vertebrates could eliminate a pest population, they appear capable of keeping pest numbers below thresholds at which damage becomes an economic problem
Vegetation change is an important tool in controlling agricultural pests. Crop species receive protection from insects when grown in association with other species through the following mechanisms: 1) reduced visibility of pest target; 2) diluted number of potential hosts with increased diversity; 3) physical interference with pest movement; 4) creation of environments which are less favorable to population buildups; and 5) creation of environments which are more favorable to parasites and predators.
On a broad scale, agricultural landscapes are composed of a large number of individual units that vary in size, shape and composition. Agroforestry must be integrated at the landscape level where concern is for the entire crop field, woodlot, fencerow, hedgerow, wetland, and orchard as a dynamic system. Each of the individual units, however, can be considered as separate ecosystems interacting with each other where plants, animals, nutrients and insects flow easily between them. In agricultural landscapes many of these flows are influenced by humans as is the case with insect pests. Insect populations in agricultural landscapes are particularly dynamic. Their spatial distribution is seldom static, with populations flowing through multiple habitats with multiple spatial patterns over the course of a season. The spatial patterns of vegetation strongly influence the biology of arthropods both directly and indirectly. In particular, corridors, that are a common feature in many agroforestry systems and distinct as narrow strips of land different from the matrix on either side, can play significant roles.
Due to their extensive edge to volume ratios, corridors harbor organisms that tend to have extensive interactions with adjacent elements. Tree and hedge rows, irrespective of their application, may increase or decrease pest density in an associated crop depending upon a number of factors. These uncultivated habitats can, and sometimes do, serve as a reservoir of pest species acting as a source of initial infestation for adjoining crop fields or orchards. These habitats may be important as over wintering sites for predators or as a source of food. Alternatively, association with wooded edge habitats has been reported to reduce the infestation of certain pests. An increased abundance of natural enemies and more effective biological control of pests is often found where uncultivated habitats, frequently corridors, occur in association with crops. Many feel that through management, the positive aspects of corridors can be accentuated while the potential negative aspects are eliminated. For example, some forest-dwelling carabids -- predators of insect pests -- are never found more than 150 feet from a forest edge. Hedgerows, however, have been shown to serve as corridors for forest carabids to penetrate as much as 12.5 miles into nonforested agricultural landscapes greatly enhancing their ability to help control pest species.20
Studies in Michigan have shown significantly higher ichneumonid wasp parasitism of European corn borer larvae near wooded edges than near non-wooded edges or field interiors. Microclimatic effects involving temperature, wind flow and shading, coupled with the spatial arrangement and proximity of adult food -- flowering plants in noncrop areas -- are believed to contribute to the higher predation.21 These and subsequent data strongly suggest that local landscape structure and its management can play an important role in pest regulation. However, careful design of species rich crop systems with field-margin vegetation or within field-plant diversity is required.
Great concern exists over the quality of our air, water and soil resources. Water and air quality and control of soil erosion have been significantly improved as a result of the application of agroforestry practices.
Agriculture-derived contaminants such as sediment, nutrients, and pesticides, constitute the largest diffuse source of water quality degradation in the United States. Surface runoff and subsurface flow from sites of farm animal waste application and crop and pasture fertilization can cause significant nutrient loading to down slope water sources unless appropriate management techniques are applied. Excessive pollutants have deleterious ecological impacts on the receiving waters of streams and lakes. Catchment strategies are advocated that use best-management practices and techniques that incorporate natural physical and biological processes to reduce, convert or store pollutants on the land before they enter aquatic systems. Bioassimilative strategies have been adopted for mitigation of the negative impacts of agricultural practices. These include the use of riparian VBS which are accepted management practices under the Conservation Reserve Program (CRP).
Riparian VBS have been adopted as a viable tool for stream and river restoration and management. Research has demonstrated that inclusion of trees and shrubs in VBS within agricultural systems can improve water quality.22 Nutrient uptake and removal by the soil and vegetation in a wooded riparian ecosystem has been shown to prevent agricultural upland outputs from reaching stream channels. The mitigating benefits of VBS are maximized if they are established in smaller headwater streams whose lengths dominate drainage networks.23
In small to mid-size streams, narrow bands of woody vegetation parallel to the stream can stabilize stream banks, moderate temperatures, reduce sediment input and provide essential organic matter sources to the lotic community. Partially as s response to the heavy flooding along the upper Mississippi River in 1993, the use of riparian VBS for stream bioremediation is expected to increase.
Woody VBS function as bioassimilative transformers, changing the chemical composition of compounds. Under oxygenated soil conditions, resident bacteria and fungi mineralize runoff derived nitrogen which is then available for uptake by soil bacteria and plants. Field-applied nutrients moving to streams and ground water are reduced due to absorption by roots within the tree/shrub/grass strip. Greater infiltration of nutrient transporting water occurs within the strip than in cultivated soil. Planting or retaining riparian VBS are effective and economically feasible procedures for reducing nitrogen and phosphorus inputs. Processes involved include retention of sediment-bound nutrients in surface runoff, uptake of soluble nutrients by vegetation and microbes, and absorption of soluble nutrients by organic and inorganic soil particles. Forested VBS 90 to 150 feet in width have been shown to reduce nitrogen in groundwater by 68 to 100% and in surface runoff by 78 to 98%. Forested VBS 50 to 150 feet wide reduce phosphorus concentrations in surface waters by 50 to 85%.23
Mature riparian forests have been shown to be excellent nutrient sinks and buffers, yet little research has been conducted on the short-term effectiveness of newly established riparian forests. However, densely planted poplar were recently established in Iowa to provide a riparian buffer for conventional row-crop agricultural land. In certain instances, the re-established riparian buffer decreased nitrate concentrations in the shallow soil profile from 25 to 5 parts per million during the first year of eatablishment.24
Biomass removal/saturation in woody VBS
Both woody and grass VBS require periodic maintenance to sustain optimal performance. Evidence points to leakage of phosphorus in woody and grass VBS due to nutrient saturation. Saturation problems with VBS can be moderated by continual harvest and careful management of the wood and grass component. Harvest of vegetation causes reversion to a state of active growth and biomass accumulation recreating a condition of high site demands for water and nutrients. Maintenance of an intermediate successional state of active growth/biomass accumulation helps maintain the VBS and minimizes loss of nutrients.25
Sediment reduction and stress bank protection
Sediment loading and deposition also contribute to water-quality problems. Both experimental and field studies indicate that narrow VBS -- 30 to 90 feet -- that augment shallow sheet flows can protect streams from excessive sediment loading and reduce sediment input to surface water. Reductions of sediment yields by woody VBS are achieved via the following mechanisms: 1) deep root systems which resist scouring under swift current conditions; 2) dense, well-ramified top growth for storage of nutrients and pesticides; 3) resistance to flooding and drought; and 4) ability for rapid recovery following heavy sediment loading. Wooded VBS have been shown to be more effective in stabilizing stream banks than grass VBS due to the deep, perennial root systems.26
Wooded VBS between 30 and 90 feet in width have been shown to reduce solar radiation inputs and effectively moderate stream water temperatures.27 The principal advantage of shading on water quality is found in the improved habitat for many aquatic insects via reduced stream water temperature, higher dissolved oxygen and reduced denitrification rates. Partial shade is preferred when attempting to maximize both the overall ecological health of the riparian environment and control specific submerged and emergent aquatic plants.
Little information exists related to the time required or the type of woody VBS needed to restore farm streams to their former undegraded condition. However, the requirement may be less than previously thought. In 1985, a woody VBS was established in southern ontario. A 1.2-mile section of a small degraded stream was planted with 6,500 hybrid poplar, silver maple, alder, black walnut, green ash and red oak trees. After only 4 years, the tree plantings averaged 8 dried tons of biomass/acre and within the poplar plantings, radiation loadings to the middle of the stream were reduced by almost 40%.28
Woody VBS act as a source of nutrients and energy for streams in the form of dissolved carbon and organic detritus. These materials help restore and maintain the aquatic food chain providing nutrients to benthic detritivores. As they are consumed by larger benthic fauna and ultimately by fish they help transfer energy up the food chain. In the southern ontario study", fish sampling documented the presence of endangered red-sided dace in 1987 and brook trout by 1990. Although the headwaters of the creek are spring fed and have a resident population of brook trout, they had not been found at this location prior to streamside tree planting.
Herbicide and pesticide reduction
Herbicides and pesticides are reduced due to decomposition resulting from organic matter in woody and grass VBS. Furthermore, the extensive network of roots within the strip serves as sites for capture and bioremediation of chemicals before the pollutants move offsite. Within the soil and litter layers of woody VBS, many toxic chemicals, including pesticides, are transformed to nontoxic forms by microbial decomposition, oxidation, reduction, and solar radiation.
Global warming resulting from the buildup of trace gasses in the atmosphere is a potential problem of major proportions for the 21st century. Projections for increases in global surface temperatures range from 5° to 15°C. A major contributing factor is the dramatic increase in ambient carbon dioxide levels. Long-term studies clearly demonstrate increases which approach 1 part per million per year. Biomass-derived carbon dioxide emissions, especially from fossil-fuel burning, account for a significant percentage of the increases I observed. Trees and other green plants require large quantities of this carbon dioxide to satisfy their photosynthetic requirements and thus serve as a carbon sink.
Although oceans store a far greater quantity of carbon than terrestrial ecosystems, at present our ability to manage terrestrial ecosystems is greater. Tree planting in conventional forestry and agroforestry programs presents many opportunities to sequester atmospheric carbon dioxide and mitigate the impacts of global warming. Young, fast-growing trees take up carbon at high rates. If the end uses of forest products are durable goods such as furniture, carbon is stored in these materials for decades or centuries beyond the life of the trees. Alternatively, woody biomass burned for energy as a substitute for fossil fuels poses an effective mechanism to reduce the depletion of nonrenewable fossil fuel-derived carbon at no net increase in carbon dioxide emissions.
Trees, as long-lived perennials, are an effective storage system for sequestered carbon and carbon dioxide.29 Studies have demonstrated that an "average tree" sequesters about 13 pounds of carbon and carbon dioxide per year. If in agroforestry, trees were planted using a 10 by 40-foot tree spacing, the spacing often recommended for alley cropping, these 108 trees per acre could potentially tie up 1381 pounds of C02 per acre per year or, assuming 60 years as the average life of these trees, 82,866 pounds per acre of carbon and carbon dioxide during the rotation. If this were extrapolated just to the millions of acres in the Conservation Reserve Program (CRP) a substantial step could be made towards mitigating the carbon dioxide problem.
A program designed to meet minimum shelterbelt planting needs for crop protection and reduced wind erosion in the United States has been estimated to result in the establishment of 1.9 million miles of woody corridors containing 1.3 billion trees on 5 million acres (Table 8). Simultaneously, these woody corridors would sequester 89.8 million tons of carbon dioxide. A more aggressive program of woody corridor establishment, designed with the goal of protecting 40 percent of U.S. cropland would require planting an additional 1 billion trees or shrubs. These additional woody plants would occupy 3.4 million acres and would sequester an additional 86.8 million tons of carbon dioxide. The cumulative benefit of such an aggressive planting program to establish 2.3 billion trees would result in sequestration of 176.6 million tons of carbon dioxide.
ECONOMIC BENEFITS
Production Economic Benefits
Agroforestry adds a significant element of diversity to an existing or planned agricultural system. The added diversity associated with such an endeavor is, in general, financially advantageous. It provides a farm operator the opportunity to develop a portfolio of short- and long-term investments thus allowing for some risk spreading through diversification. In addition, for some farmers with land particularly unsuitable for crop production, agroforestry provides an avenue for that land to be removed from crop production over an extended period of time as the trees mature. Likewise, agroforestry produces economically valuable social benefits, some directly measurable, others not, by ensuring resource conservation.
Agroforestry, from a production economics standpoint, is representative of the multiple output model where several fixed and variable inputs are combined to produce at least two products. Implicit in this model is that quantities produced of all outputs can be varied by deliberate management decisions. Thus, one of the objectives in agroforestry is to achieve production efficiency -- optimization of the combination of inputs and outputs in attaining a stated production objective over a given time period. Simply expressed, the typical adoption decision is to add trees to the land as long as the increase in overall benefits from each additional tree is greater than the overall benefits foregone from the crop which the tree is replacing. The optimal point of output combination of trees and crops is where additional trees (or crop) when substituted for the other product leads to a decline in the overall benefit through time.
Various agroforestry systems have been evaluated on a financial basis for both production and protection. A number of these systems are described and their economic aspects discussed.
In the Midwest, the most common tree/crop system studied has been alley cropping. Due to growing conditions and markets, openly spaced systems containing high-value hardwoods typically have been examined. The open condition has led to concern regarding the quality of agroforestry-grown wood. However, early indications suggest no adverse effects on wood quality. To the contrary, parameters such as height, diameter and specific gravity benefit. Moreover, based upon early growth rates, a 50 to 60-year veneer log rotation is projected for trees grown under alley cropping instead of the customary 80 to 100 years.30
Numerous economic assessments have been conducted on agroforestry management regimes incorporating agricultural crops with trees. Alley crops shown to be viable from both economic and biological perspectives include soybeans, corn, milo, wheat, cool-season forages, sod species such as bluegrass, energy plantings such as sycamore, poplar and silver maple, and livestock. Typical internal rates of return range from 4 to 11%.31 In general, returns tend to increase with management complexity and site quality. However, obvious factors such as market value of the crops grown, cash-flow relationships and even risk-taking influence profitability. Tree species which yield especially high-value wood products, along with fruit or other marketable products, have obvious advantages over low-value species which produce only wood products. Enterprises such as livestock grazing have shown great potential but also carry a degree of risk due to the increased chance of tree damage. Further, an increased investment-must be incurred early in the rotation for fence construction and maintenance if grazing is to begin immediately following tree establishment.
Findings of special interest have been reported from Illinois where interplantings of black walnut with various common crops were accomplished using conventional tillage, minimum tillage and no-till. The primary purpose of the work was to ascertain the economic viability of agroforestry systems for marginal quality soils. Black walnut in an agroforestry management regime was found to produce land expectation values comparable to those of traditional agricultural systems, particularly at the lowest discount rate of 4%.32 Another option on marginal quality soils is to plant nitrogen-fixing nurse crops, such as black alder or autumn olive, with commercially valuable tree species to reduce managerial inputs and enhance growth. Reports suggest that valuable tree species interplanted with nitrogen-fixing trees offer an economically viable alternative to conventional row crops on marginal lands.33
Several agroforestry management systems involving integration of natural stands of timber with grazing have been evaluated in terms of their physical inputs and outputs. However, little information has been published on the, economic costs and benefits. In the southern coastal plain, research on grazing longleaf-slash pine forests over a 40-year rotation has shown average annual net returns of $7.64 per acre for the grazing operation and $87.56 per acre for the timber.34 In studies of domestic forages established under 20-year old loblolly pine and evaluated over a 5-year period, two out of five alternatives considered yielded greater internal rates of return than the open-grown forage alternative.35
To evaluate a system incorporating deferred grazing to enable tree establishment, a system of haying for the first three years followed by grazing for the next three was evaluated under slash pine.36 Wide spacing permitted harvesting hay for forage while waiting for the trees to become large enough to permit grazing. This system was found to provide early, regular returns for the landowner and eliminate the need for internal fencing. Yet another potentially valuable product coming from pine stands is pine straw needles) used as a mulch in landscaping. Recent developments in the pine straw industry permit landowners to supplement their income through agroforestry systems designed to include pine straw harvesting every few years. With prices in excess of $100 per acre being paid, combinations of wood, forage, livestock and pine straw can yield attractive financial gains. Furthermore, financial analyses of the incremental gains in pine straw production associated with investments in nitrogen and phosphorus fertilization have demonstrated that intensive management of stands is financially profitable.37
Protection, as discussed earlier, is one function of an agroforestry system. Economically, the loss of soil and chemicals from the land are problems that impact society as off-site "externalities." That is, their costs are not incorporated into the production decision framework by the individual on whose farm they originate.
Adoption of practices that will result in a measure of protection benefiting society are borne by the landowner, unless society is willing to share the cost and responsibility through some form of assistance. An example is the Conservation Reserve Program (CRP). An evaluation of benefits emanating from the CRP suggest that some $6 to $14 billion in present value could result if its full enrollment goal of 45 million acres were achieved.38 39 A scenario in which 10$ of the acreage enrolled by 1990 was in trees resulted in higher water quality benefits than a baseline comparison. Further, policies to reduce soil loss were found to improve wildlife habitat as well as increase water quality through reduction of sediment delivery to streams.
Adoption of agricultural conservation practices for the benefit of society at large by a farmer who must absorb a large portion of the initial coat is not likely to occur often, even if over the long term the farm operator realizes a net benefit. Economically rational farm operators are more likely to adopt conservation practices which benefit them directly and in the more immediate future. A policy interpretation of the results of a cross-sectional, time series study of farmers' investments in land improvements found that farmers invest in land improvements in response to expected increases in income. Farmers have an added incentive to invest in conservation practices if farmland prices increase relative to the cost of improvements. Furthermore, government programs that idle land during the growing period provide an incentive for added investment.40
Some farm operators, however, for non-economic reasons, adopt conservation practices that do not yield immediate, short-term benefits. Investment in conservation measures other than conservation tillage has been found in certain instances to be positively related to perception of an erosion problem, farm size, income and existence of a conservation plan. Furthermore, some studies have found that a sense of stewardship relative to protection of natural resources has a positive relationship to farmers' use of conservation practices.
On-farm soil erosion which generally proceeds at an imperceptible rate can exact a gradual but heavy toll on a farm business. Perhaps the most noticeable effect of erosion, from the farmer's standpoint, might be in the cost of fertilizers. It has been reported that a loss of five tons of soil per acre per year, within the tolerance limits of many soils, requires an annual addition of $24 per acre of commercial fertilizers to maintain production levels.41
Moreover, as a result of erosion, the lives of reservoirs are shortened as they fill with sediment. Estimates of the cost of cropland sediment in reservoirs run as high as $200 million annually.42 The largest costs occur in the northern plains and corn belt regions where water storage capacity is least. In these two regions, nearly two-thirds of the sediment entering reservoirs comes from cropland. Communities that rely on reservoirs for residential water supplies must remove the sediment in the process of purifying their water. In Ohio alone, studies show that a 25% reduction in soil erosion would result in a savings of $2.7 million in water treatment costs each year.43 Such findings imply even greater savings for areas experiencing excessively high erosion rates.
Financial aspects of using agroforestry rather than mechanical means to control erosion have been evaluated in Missouri. Three "representative farms" of different sizes containing a composite mix of the most common soils in the region were developed and several agroforestry systems along with terracing and grass strip cropping were simulated for each farm size to reduce soil erosion from typical crop rotations on the highly erodible soils to tolerance (T) levels. Tree species planted included black walnut for timber and nuts, Scotch pine for Christmas trees, and American sycamore for industrial fuelwood. Agroforestry enterprises were found to be more profitable than using conventional erosion control measures.44
The economic benefits of shelterbelts are quite variable and location specific due to the indirect nature of their contribution. While numerous studies have been published describing the specific gains in increased crop yields, few financial evaluations of the costs associated with generating the gains are available. A detailed examination of the financial aspects of several field windbreak systems over a range of crops, yields, prices, discount rates, and windbreak establishment costs has been conducted for eastern Nebraska. Three systems utilizing windbreaks at spacings of 635, 420, and 218 feet were evaluated in fields planted to either soybeans, winter wheat or corn. All three designs were found to yield positive net benefits over an estimated 50 year life span. The lowest return was from the widest spacing, although a positive present net worth at a 11% discount rate was still realized. Positive were yielded by the other designs at discount rates as high as 17%.45
Three general benefits of an economic nature are typically ascribed to agroforestry. They are spreading (sharing) of fixed costs because of the joint-production relationship; reduction of the initial time period required for income from land devoted exclusively to tree production; and diversification of income sources, in effect spreading the risk generally associated with a monoculture. Likewise, from an operational standpoint, agroforestry to some extent increases flexibility in agricultural operations since many silvicultural practices may be delayed with little or no detrimental effect until free time is available. Of additional importance, however, is that agroforestry offers a means by which farmers can phase out some or all of their row crop production over time, at a rate approximating the rate of depreciation of their farm equipment.
Agriculture, forestry and rural development policies at federal, state and local levels have important effects on the development of agroforestry and realization of its benefits. Numerous policies within these broad arenas and limited provisions that are aimed directly at agroforestry will influence the allocation of resources to this activity by landowners, public institutions and non-profit membership groups. While it is beyond the scope of this effort to analyze or even identify the full range of policies that may affect agroforestry in its broadest sense, the following discussion highlights programs and traditions in key institutions that appear likely to influence agroforestry development most directly.
The Food, Agriculture, Conservation and Trade Act (FACTA) of 1990 contains two
explicit provisions for agroforestry.
Conservation Reserve Program (CRP)
The Conservation Reserve Program as established by the Food Security Act of 1985 offers agricultural producers long-term rental agreements, acreage payments and cost-share assistance to establish permanent vegetative cover on selected cropland. The Conservation Program Improvements Act (Title XIV of Food, Agriculture, Conservation, and Trade Act of 1990 - FACTA) amends the 1985 act to allow cost sharing for alley cropping of agricultural commodities when such land is planted to hardwood trees, provided that operators offer to reduce annual rental payments by 50% in exchange for permission to produce agricultural commodities. It also provides for windbreaks and shelterbelts without requiring enrollment of the entire field and allows the operator to specify, within limits, the terms of such contracts for these features.
Center for Semi-arid Agroforestry (CSA)
The Forest Stewardship Act of 1990 (FACTA - Title XII - State and Private Forestry, Ch. 2, Sec. 1243) provides for the establishment of a Semiarid Agroforestry Research, Development and Demonstration Center (Center for Semi arid Agroforestry). Through participation by federal or state governmental entities, land grant colleges and universities, state agricultural experiment stations, state and private foresters, the National Arbor Day Foundation and other non-profit foundations, the Center is charged with conducting research to develop sustainable agroforestry systems on semiarid lands in 17 western states. Such systems are intended to minimize topsoil loss and water contamination and stabilize or enhance crop productivity.
A broad set of specific objectives and activities is identified for this specialized research including biological, sociological, demographic and economic studies aimed at increasing the use of improved forestry conservation and agroforestry practices. In addition to in-house and cooperative research, the Center is charged with transferring agroforestry technology to state forestry agencies, the U.S. Department of Agriculture's Soil Conservation Service (SCS), soil conservation districts and other state and federal agencies and organizations. It also is to conduct cooperative demonstrations of agroforestry practices and integrated conservation systems under different climatic and soil conditions that will provide opportunities to introduce new plant materials from tree improvement programs and SCS plant materials centers. Finally, it is to conduct information and education programs in concert with the National Arbor Day Foundation.
Operationally, the CSA encourages the development of state agroforestry programs which would identify goals and priorities for that state and provides some resources for attaining them. The Center would complement state activities by conducting or funding some research, cost-sharing needed demonstrations and providing technology transfer and education to meet local needs. Likewise, CSA activities are intended to complement Soil Conservation Service tree-planting programs by enhancing the traditional U.S. Department of Agriculture's Forest Service role of conducting research on trees for agricultural lands. CSA aims also to enhance the Forest Stewardship Program by increasing understanding and acceptance of the benefits of tree planting on agricultural lands.
Funds for the Center, however, have not been appropriated. Therefore the Center's core operating expenses, which in 1992 amounted to $350,000, have been drawn from allocations to pre-existing Forest Service programs within the research, state and private, and international branches. Project funding is sought from outside the Center on a competitive basis as opportunities are identified.
Given the Center's extremely limited funding base, the Forest Service has directed the Center to limit its research and development focus for the present time to the 10 Great Plains states, but to remain an advocate for agroforestry in the westernmost semi-arid states as well. Cooperative projects in which the Center is presently engaged focus on: 1) developing more stress and pest-resistant multi-purpose trees for agroforestry systems; 2)modeling agroforestry systems in the context of global change; 3) developing riparian buffer systems; 4) identifying interactions between agricultural crops, insects and birds in agroforestry systems -- in the context of a neo tropical migratory bird study; and 5) developing cooperative agroforestry research and development with scientists in northern Mexico.
South Central Family Farm Research Center
The U.S. Department of Agriculture's, Agricultural Research Service (ARS) initiated an agroforestry systems research program at the South Central Family Farm Research Center in Booneville, Arkansas in 1992. Through the reallocation of in-house ARS funds, an initial funding level of $240,000 per year was established. The program's aim is to devise and assess agroforestry systems that are compatible with combined livestock, tree, pasture and wildlife production, and evaluate the biological, ecological, environmental, and socio-economic interrelationships among the combined multiple resources.
Related Federal Technical Assistance and Cost-Share Programs
Stewardship Incentive Program (SIP)
FACTA's Title XII (State and Private Forestry) also authorizes the cooperative Stewardship Incentive Program to stimulate enhanced management of nonindustrial private forest lands through cost-sharing of approved practices. The program is authorized to spend up to $100 million annually through 1995. For fiscal year 1991 the appropriation was $19.9 million. The 1992 fiscal year appropriation was $19.7 million.
SIP provides cost-share assistance if non-industrial private landowners have developed an approved forest stewardship plan. Approved activities and practices eligible for cost-share assistance in each state include establishment, management, maintenance and restoration of forests for shelterbelts, windbreaks, aesthetic quality and other conservation purposes as well as a range of productive purposes.
Forest Service and state foresters have leadership responsibilities for SIP at the national and state level, respectively. Each state forester in consultation with the State Forest Stewardship Committee will determine the cost-share levels, practice priorities and minimum acreage requirements. The U.S. Department of Agriculture's, Agricultural Stabilization and Conservation Service (ASCS) provides administrative assistance by accepting applications and arranging for disbursed payments. Technical responsibilities for SIP practices may be assigned to other agencies and resource professionals through memoranda and cooperative agreements with SCS and the U.S. Department of Agriculture's, Cooperative Extension Service serving as key partners in developing and implementing SIP.
Forestry Incentives Program (FIP)
The Forestry Incentives Program was authorized by Congress in 1973 under (Title X) the Agriculture and Consumer Protection Act and in 1974 was implemented through the U.S. Department of Agriculture's, Agricultural Conservation Program (ACP). In 1975, FIP became a separately funded program. A total of 3 million acres have been planted on nonindustrial private lands under FIP through 1992. FIP is distinguished in that its primary objective is to increase national timber supplies through authorization of cost-share payments for reforestation and timber stand improvement, firebreak construction and site preparation for natural regeneration.
The ASCS has responsibility for program administration while the Forest Service takes the leadership role for technical assistance. State service foresters approve landowners forest management plans and their performance of practices before payments are made. The county ASCS committee has the power of final approval of applicants to receive funding. FIP could serve as an excellent model for a national agroforestry incentives program.
Agricultural Conservation Program (ACP)
The long-standing ACP, among other activities, provides cost-share assistance to agricultural producers for tree planting to meet conservation objectives. The ASCS subsidizes tree cost to farmers and makes them available through nurseries. The program is consistent with the goals of agroforestry and marks a comparatively long tradition of ASCS and SCS involvement in promoting tree based conservation practices. Compared with other conservation measures that the ASCS has encouraged under the ACP, however, trees have played a minor role.
Environmental Easement Program (EEP)
Chapter 3 of the Agricultural Resources Conservation Program (Subtitle C of FACTA) authorizes an Environmental Easement Program. This program provides for public acquisition of permanent or long-term easements from willing owners of eligible farms or ranches to ensure the continued conservation and improvement of soil and water resources. In return for the creation of an easement on qualifying lands, landowners are prohibited from harvesting or selling Christmas trees or nuts, though allowed to undertake customary forestry practices such as thinning, pruning or tree-stand improvement. The terms of such easements also limit the production of any agricultural commodities except as they will benefit wildlife, and prohibit harvesting, grazing or other commercial use of forage.
These EEP provisions not only fail to take advantage of the potential for agroforestry to help accomplish the program's conservation objectives, but uniformly limit the owner's range of options for implementing the requisite natural resources conservation management plan. By summarily excluding practices that incorporate the foregoing components, opportunities are lost for the landowner to generate income which in turn could help reduce federal expenditures on conservation. A re-examination of the justification and the practical basis for the exclusion of agroforestry-type practices appears warranted.
Tree Planting Initiative
The EEP provides also for a Tree Planting Initiative to encourage reforestation of marginal agricultural lands, promote tree planting to reduce soil erosion, improve water quality and provide for the sustained production of the commodity and non-commodity resources that these lands can provide to meet the nation's needs. Under the Initiative, the Secretary of Agriculture is encouraged to use the following programs to accomplish this policy: Conservation Reserve (1985), Agriculture Conservation (1970), and Cooperative Forestry Assistance (1978) and provisions of State and Private Forestry (Title XII, FACTA).
Indeed, a principal intent of the initiative is to foster collaboration among agencies and programs concerned with the protective and productive roles of trees in agricultural areas. It thus could have a direct and beneficial role in assisting the development of agroforestry practices provided that technical assistance providers from the respective agencies are adequately aware of the potential roles and benefits of agroforestry in addressing the initiative's objectives.
Sustainable Agriculture Research
Title XVI of the FACTA provides for sustainable agriculture research, where sustainable agriculture is defined as "... integrated systems of plant and animal production practices having a site-specific application that will, over the long-term -- satisfy human food and fiber needs, enhance environmental quality and the national resource base upon which the agricultural economy depends, make efficient use of non-renewable resources and on-farm resources, integrate natural biological cycles and controls, sustain the economic viability of farm operations and enhance the quality of life for farmers and society as a whole ..." This mission speaks directly to potential roles for agroforestry. Known presently as Sustainable Agricultural Research and Extension (SARE), the program to date has funded few research projects that focus on either agroforestry or on farming systems that include active tree components. Greater recognition of agroforestry by this program could have an important effect. The conventional one-to-three year time frame for the completion of studies, however, constrains the investigation of many key agroforestry topics and questions.
Government Price Supports and Taxes
U.S. agricultural policy rests on a complex system of price supports and taxes which, among other objectives, aim to influence production levels and consumer prices for respective commodities. Income tax provisions and price supports are highly influential in the use and management of agricultural and private forest lands. In addition to stabilizing markets, an increasingly important use of agricultural policy instruments during the past decade has been to limit the production of certain commodities in order to reduce "problems" of overall surplus. Since 1990, loans, payments and acreage reduction programs have placed additional emphasis on conserving soil sad water resources for lands withdrawn from production.
However, the surplus production of high-value timber in the United States has not occurred and all indications are that the value of wood and wood products will continue to grow appreciably. A policy focus on growing high quality timber under field or pasture conditions in agroforestry systems provides an opportunity for government to overcome problems of commodity surplus without having to subsidize growers to produce less. It will be critical to the promotion and development of agroforestry that markets for key tree crops produced in agroforestry systems, and nuts in particular, are encouraged to flourish despite projected increases in levels of production.
Federal tax policy with respect to forestland has aimed principally to limit the financial burden of management on the private landowner. And, the policy, through capital gains provisions of the income tax, helps to syncopate the incidence of taxation with the realization of profit from timber sales. Certain state tax laws provide further incentives to landowners to undertake forest management. This is achieved not only through the state income tax, but also by allowing the deferment of property taxes on lands under active forest management until a significant volume of timber is harvested or until the property is sold or transferred.
Policy instruments to encourage agricultural conservation include federal income tax provisions that allow farmers' soil and water conservation costs to be expensed rather than capitalized as long as the measures have been approved by the SCS or comparable state agency.46 This would include tree planting costs. In addition, payments farmers receive for certain conservation and environmental protection programs may be excluded from income. This includes payments for purchase and installation of capital improvements and the implementation of best-management practices, except for payments that are expenses on Schedule F (the federal income tax form for profits and loss from farming).
In addition to these various income tax exemptions, deferments are allowed for farmland owners who enter into permanent easement agreements for various conservation purposes. Such allowances are based on the decline in the value of such properties to the owner.
It is evident that there is adequate precedent in the use of policy instruments that could encourage landowners to invest in agroforestry. on the other hand, the effect of more widespread application of agroforestry as a conservation device on public subsidy and tax programs has not been evaluated. It could be hypothesized for example that, over time, a combination of public education about the benefits of agroforestry and minor adjustments in income and property tax policy would reduce the need for direct public subsidies for production reduction and natural resources conservation.
Agroforestry Research, Extension and Education at Land-Grant Universities
There are no provisions in the enabling legislation for land-grant universities or for Cooperative Extension Service that would prohibit or limit agroforestry research, extension or education. Indeed agroforestry programs are developing at a number of land-grant institutions and interest in agroforestry at universities and colleges throughout the nation is increasing. Generally, such programs have emerged from departments of forestry or natural resources. Successful programs, however, are highly interdisciplinary and involve faculty, staff and students from a range of departments and state agricultural experiment stations. Furthermore, they depend on successful integration of research and extension early in the research process due to the critical role of landowner input and feedback in the comparatively complex and long-term studies required.
Among the most longstanding and rigorous agroforestry research, extension and education programs are those at the Universities of Missouri and Florida, State Universities in Michigan, Washington, Colorado and Iowa, and Cornell University in New York. The emergence of agroforestry as a domain of knowledge generation at these institutions has depended however on the vision, energy and determination of a few key individuals. These individuals have directed scarce research and education resources to agroforestry despite the absence in most cases of funding dedicated specifically to these activities. Further growth of these programs is limited directly by lack of recognition by policy decision-makers and the associated lack of funds.
For faculty who are not tenured, significant involvement in agroforestry research and education can pose risks to their institutional security due to the still marginal statue of agroforestry as a scholarly or practical pursuit. Due to the complex and long-term nature of much agroforestry research, on-farm methodologies are often the most practical and sometimes the only feasible means of answering many of the relevant questions. Certain constituent disciplines, however, may question the robustness of such research designs. Thus, young faculty members who may be enthusiastic about agroforestry are also concerned about jeopardizing their credentials and may fail to pursue research or teaching in this field.
Agroforestry's continued marginal status with respect to funding and program development at leading land-grant and other academic institutions throughout the country stems partly from insufficient recognition of agroforestry as a domain of professional practice. Until public agency positions for "agroforesters" are identified, it may not appear justifiable to academic administrators to invest in the education and training which in turn could support extended research programs. In the meantime, there is a common perception among the comparatively few professionals who do identify with agroforestry that resource managers are not receiving the training needed to provide adequate technical assistance in integrated resource management.
State Agroforestry and Related Programs
Missouri, in 1990, was the first state to adopt specific agroforestry legislation. Designed to complement the extended CRP, Missouri's agroforestry legislation is limited to alley cropping defined as the use of trees planted or otherwise established on land with grass strips or row crops or both between the lanes. Based on the demonstrated effectiveness of this technology in controlling soil loss from highly erodible land in Missouri, state policy makers sought to encourage more landowners to enroll greater acreages in alley cropping than would have come about through federal incentives alone. The state initiative compensates farmers for the difference between payments they would have received by adopting a non-agroforestry CRP practice and the amount allowable -- 50% reduction in rental payments -- for alley cropping
The legislation makes no explicit provisions for agroforestry research or extension. The University of Missouri, however, has perhaps the best developed agroforestry research and extension program in the United States. Indeed the state's innovative agroforestry legislation and landowner incentive program can be attributed in large part to the strength of this program.
Since 1990, South Dakota and Iowa have followed Missouri's initiative in providing added incentives for CRP enrollees to adopt agroforestry practices. Illinois' Forestry Development Act authorizes cost sharing for tree planting which is not tied to CRP, and presently has legislation pending which would further subsidize CRP tree planting.
Association for Temperate Agroforestry (AFTA)
As a result of the diverse interest in agroforestry, academic, agency professionals and landowners joined together in 1991 to form the Association for Temperate Agroforestry. This growing society provides an umbrella for temperate agroforestry activities via networking and information-sharing services to its members. AFTA was formed as an outgrowth of biennial conferences on temperate zone agroforestry that have been held since 1989. AFTA is now their primary sponsor. The conferences have been instrumental in the intellectual and the practical development of agroforestry. In recognition of the multidisciplinary and interagency perspectives that effective agroforestry development requires, from the beginning these meetings have included landowners and agency professionals as well as academic representatives.
Non-profit membership groups
There is a vast though often unarticulated network of membership groups who are sympathetic to agroforestry and sometimes actively engaged in its development. Associations of forest owners, Christmas tree, nut or fruit producers, shiitake mushroom or ginseng growers, bee keepers, fallow deer and other alternative livestock farmers, organic growers, permaculture designers and various conservation and environmental organizations have members who consciously practice agroforestry and many more who manage land and resources by means that are consistent with agroforestry principles.47 Presently, there is no consistent public policy that unites these groups in purpose or provides incentives for them to promote or support agroforestry development.
Given the ubiquity of such groups throughout the country, the often innovative character of their membership, the important educational role they play on behalf of their members and the public, and the spirit of volunteerism that infects moat such groups, public policy that would direct and support their activities in agroforestry is likely to have early and far-reaching payoffs. Well-designed, small-grant programs directed at such groups, perhaps incorporating some linkage with land-grant managed research and extension, are likely to generate the type of practical knowledge and information needed to significantly enhance agroforestry innovation and adoption nation-wide. Small grants may also be used beneficially to enhance the synergy among respective membership groups whose dominant agendas presently do not warrant their direct interaction. Few if any incentives are available for these groups to help develop and promote agroforestry. Providing such incentives on a competitive basis would likely have a significant impact at comparatively little public cost.
Summary of Policy Relating to Landowner Incentives
Programs that provide cost-sharing incentives have been highly effective with respect to stimulating landowner interest and enrollment. The CRP program has become competitive and is fully subscribed. Furthermore, many of the practices encouraged by the program, particularly those with tree-planting components, are now viewed to have cumulative environmental and economic benefits well beyond those anticipated by program planners. Thus, there is considerable speculation and planning at present concerning the future of CRP lands and the potential for using agroforestry as a mechanism that is attractive to land owners for continuing CRP-type practices after present contracts have expired.
The Conservation Reserve Program, however, excludes many joint crop/animal and tree production options and remains narrowly focused on alley cropping, windbreaks and shelterbelts. CRP could be more attractive to landowners if certain barriers to joint production were relaxed, especially those involving grazing, and if the minimum number of trees per acre was reduced to better accommodate agroforestry practices or fully stocked tree plantations. The Stewardship Incentive Program, unlike CRP, has given no explicit consideration to agroforestry practices. However, like the CRP, in many states SIP enrollment is fully subscribed. The program however is young and its direct benefits remain to be evaluated.
There is a lack of general knowledge of the implications of state and federal taxes and price support policies for land use in general, and agroforestry in particular. While such phenomena may be understood by agricultural economists I and related professionals who study them, there is a need to make these linkages more transparent so that technical assistance providers and landowners can factor them into long-term management strategies more effectively. Likewise, it is important that the role of subsidies and taxes in landowner decision-making about agroforestry be systematically evaluated, and that the role of agroforestry in reducing the need for public subsidies for conservation be examined.
Furthermore, it is extremely important that obvious disincentives to the practice of agroforestry be re-evaluated in light of what is known about its benefits to conservation. In particular, the Environmental Easement Program should be considered not only with respect to the prohibition of certain agroforestry-type land uses, but also in terms of public subsidy reductions that may be possible by incorporating agroforestry into this program.
The need and potential for agroforestry land use systems throughout the United States is becoming increasingly well documented through scholarly research as well as agency mandates and program evaluations. However, a host of real and perceived problems relative to education/information, research and policy must be addressed and resolved before the full potential benefits of agroforestry can be realized. These problems are:
Education/information
1) a high level of uncertainty and accompanying risk associated with agroforestry as an unproven land use system;
2) the perception of high establishment costs and level of management expertise required;
3) a perception that the economic gains from agroforestry are lower than from more traditional production agricultural practices;
4) an unwillingness to adopt systems with rotation lengths which may exceed the landowner's life expectancy;
5) a perception by many agencies that landowners would be unwilling to follow management prescriptions necessary for developing and maintaining economically and ecologically profitable agroforestry systems;
Research
6) a weak basic and applied research base to support agroforestry management decisions;
7) lack of a strong research, teaching and extension infrastructure committed to agroforestry;
8) minimal opportunities for graduate study which emphasizes domestic agroforestry and minimal employment opportunities for trained agroforesters;
9) an inability to recruit young scientists due to the dearth of funding and a perception that applied research is not sanctioned or rewarded in academia;
Policy
10) exclusion of agroforestry by current public cost-share programs due to minimum acceptable tree planting densities, and the lack of federal policy relating specifically to agroforestry; and
11) a resistance from organized commodity groups who feel subsidized producers entering the market through federally funded programs, such as CRP, represent unfair competition.
ACHIEVING AGROFORESTRY'S POTENTIAL
In view of the problems facing today's landowners and our nation, and the emphasis being placed on developing sustainable agricultural and natural resource systems, agroforestry can have lasting environmental and social impacts. To realize this potential will require a concerted effort on the part of many, including established agricultural and natural resource institutions ouch as land-grant universities and USDA agencies. Through a unified effort to enhance our knowledge of agroforestry and to extend knowledge already available, many of the current constraints to the adoption of agroforestry would disappear. The first priority should be to provide national leadership in the form of an agroforestry coordinator. The designee, a USDA employee, would coordinate agroforestry activities in research, education, extension and policy while networking agencies and institutions working within this field.
Agroforestry systems and techniques are beat developed in an interdisciplinary I context through regular and interactive participation by scientific researchers, technical specialists from respective fields and agencies, and landowners. Thus, programs are needed that explicitly combine conventional research and extension functions in a holistic manner and that actively involve landowners in establishing and implementing research agendas.
The second priority is to secure funding for agroforestry. A major limitation to agroforestry research, teaching and extension is the lack of funding available due to disciplinary boundaries. Agroforestry is a hybrid field and, as such, receives only a fraction of the funds available to the parent disciplines of forestry and production agriculture. Funding for agroforestry need not be through new programs, although new monies are an option. Many existing programs could accommodate agroforestry if sufficient resources, specific directives, and administrative will existed. The requirement is that dollars be earmarked specifically for agroforestry programs which adhere to the strict definition of this field of study.
Some agroforestry technologies are already well enough developed for broad implementation but are not being widely applied, often due to the lack of technical assistance available to the landowner. Opportunities exist for land-grant universities, Cooperative Extension Service, SCS and Forest Service, as well as state and local agencies and private entities, to provide consultation and informative materials to better guide landowners and land managers in implementing agroforestry practices. Technical advisors may recognize the need for such programs but often lack the expertise required to implement them. Hence, training for technical advisors would enhance implementation of agroforestry practices.
Furthermore, in the medium term there will be a need for more and better developed agroforestry curricula at the undergraduate and graduate levels, particularly if the land-grant system and related resource management agencies establish a stronger focus on agroforestry development. The enormous and growing interest in this field by students is an important indicator of the likelihood that agroforestry education will improve as research and practice develops. For this to occur, however, it is critical that each reasonably distinct "agroforestry region", or collection of states with similar agroforestry needs and potential, generate the resources necessary to conduct long-term, interdisciplinary studies in which students can meaningfully participate. This in turn requires a university-level commitment to allocate state resources to the establishment of secure faculty positions in this field.
A compelling argument can be made for public support of agroforestry practices. Many of the benefits -- atmospheric carbon dioxide reduction, cleaner water, erosion control, increased biodiversity -- affect all people. Currently, however, the landowner or manager bears the cost of implementing agroforestry although the landowner may not be the primary beneficiary. To optimize public benefit, some form of cost-sharing may be appropriate for those practices shown to provide real and necessary public benefits. It is critical to evaluate our system of subsidies and taxes and identify measures that encourage more and better agroforestry practices. During the process, it is important that we develop agroforestry land-management systems that are sufficiently attractive financially for landowners to adopt on their own merit. Such is and should continue to be a central goal in research aimed at developing sustainable agroforestry systems.
To further encourage agroforestry it will be important that federal income tax Schedule F -- as completed by agricultural producers with gross sales of more than $10,000 per annum -- provides that the incidence of taxation is syncopated with market receipts, rather than the overall value of the enterprise. In general, income tax provisions that presently apply to forest owners should be evaluated for their applicability to agricultural producers who incorporate a significant tree component into their enterprise for conservation and/or productive purposes. Depending also on the projected state or local level benefits to be realized, property tax codes may warrant redesign to compensate owners for creating positive "externalities".
SUMMARY OF AGROFORESTRY DEVELOPMENT NEEDS
Agroforestry provides the landowner the opportunity to develop a portfolio of short- and long-term investments which, with the proper combination of trees/shrubs and crops/livestock, provides both economic and environmental benefits. However, full implementation of agroforestry within the United States will require the development of an extensive agroforestry infrastructure (research, teaching, extension and policy). This infrastructure must be established with the ultimate user, the landowner, in mind and designed to provide a rapid turn-around of systems research findings.
Achieving the goal of full implementation will require:
a) collaborative and flexible yet adequately coordinated and empowered institutional mechanisms for planning and managing agroforestry development activities;
b) funds earmarked specifically for agroforestry land use to address the interdisciplinary and often long-term nature of agroforestry research and the multi-dimensional, inter-sectoral nature of effective technical assistance and technology transfer; and
c) modified perspectives among public agencies concerned with land and resource management which recognize the demonstrated and potential benefits of agroforestry throughout the country to address conservation and sustainable development objectives often at considerably less cost than the dominant alternative strategies.
A "Commission an Agroforestry" should be established to determine the role of agroforestry in the United States. This commission should be charged to:
a) identify broad national and more focused regional agroforestry needs;
b) determine research, teaching and technology transfer requirements to satisfy those needs; and c) recommend policies and programs required to ensure that the future needs are adequately and efficiently met.
In view of the current level of interest in agroforestry as a land-use system, and the degree of urgency associated with implementing certain agroforestry practices to improve environmental quality, an interim strategy is proposed and presented here.
a) The USDA Soil Conservation Service should assume a role in eliminating the barriers to more widespread and effective agroforestry practice. The SCS's long-term professional leadership position in farmland conservation technology development and implementation, its prominent collaborative activities with other resource management entities in many states and its physical presence at a local level throughout the country, places the agency in a strategic position to assist in agroforestry development.
b) Annual funding of $15 to 25 million should be established to support agroforestry research, teaching and outreach programs throughout the country. The funds should be allocated to the many forms of education, technology development and transfer needed to adequately enhance the agroforestry knowledge and information base among resource management agencies, land management professionals, policy makers and landowners.
c) A broad and flexible institutional mechanism should be established to routinely assess agroforestry development opportunities and priorities throughout the country and to allocate funds earmarked for agroforestry on a competitive basis. The following two-tiered strategy is proposed:
Federal level -- A National Agroforestry Advisory Board could be established within the USDA. An agroforestry coordinator would be designated as a full time director to facilitate the activities of the board. The board and coordinator would advise regional agroforestry consortia. Members also would advise their respective parent organizations on strategies for enhancing agroforestry development in the context of their on-going programs. The board would be comprised of representatives of USDA and other agencies, institutions and private organizations with key expert and facilitative roles to play in developing agroforestry. The board would monitor and help coordinate activities of the regional consortia including "vision-sharing", education, professional training, research, technology transfer and policy development. Initially, the board could sponsor a national-level workshop to identify key opportunities for linkage among regions as discussed below.
Regional level -- Consortia could be developed within "agroforestry regions" which link USDA professionals with land-grant universities and other sources of research, technology transfer and technical assistance capability within the region. Such consortia would recommend funding for agroforestry development by regions. Each consortium would develop an agroforestry plan that reflects research, technology transfer and technical assistance needs and development priorities. The priorities would be incorporated into guidelines for education, training, research, technology transfer and policy development project proposals. Consortium members could draw upon expert review panels convened to assess the merit and feasibility of implementing the respective proposals in that region.
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User Rating: 4 / 5
A NATIONAL REPORT
Edited by
Miles L. Merwin
Association for Temperate Agroforestry
1997
H.E. "Gene" Garrett, President
School of Natural Resources
University of Missouri
Columbia, Missouri
TABLE OF CONTENTS
II. Background, Purpose and Acknowledgements
III. Agroforestry Concepts and Practices
Key Characteristics of Agroforestry Systems
Current Status of Agroforestry Systems
Agroforestry and Farm Management Planning
Practices Which Are Not Agroforestry
IV. Issues, Needs and Recommendations
Needs, Opportunities and Recommendations
V. Summaries of Regional Assessments
AFTA defines agroforestry as an intensive land management system that optimizes the benefits from the biological interactions created when trees and/or shrubs are deliberately combined with crops and/or livestock. There are five basic types of agroforestry practices today in the US: windbreaks, alley cropping, silvopasture, riparian buffers and forest farming. Within each agro- forestry practice, there is a continuum of options available to landowners depending on their own goals (e.g., whether to maximize the production of interplanted crops, animal forage, or trees).
Landowner Adoption
Farmers, ranchers, and foresters may not recognize particular practices as "agroforestry" even though they make use of them (e.g., field windbreaks to protect crops). Agroforestry is a set of practices integrated into larger land use systems. It is not a product or commodity. As a part of integrated land use management systems, agroforestry is relevant to the sustainable production of a wide variety of agricultural commodities, as well as the production of high-value specialty products.
Economic gain is the primary motivating factor in the adoption of agroforestry in the US. The decision whether or not to adopt an agroforestry practice depends on the decision maker's perception of how that practice compares with alternative land use options. To be acceptable, agroforestry practices must offer (1) at least as much income potential, without significantly greater risk, compared to other market-driven land uses, or (2) better prospects for solving a particular conservation problem compared to other practices that do not involve tree planting. While economics are often paramount in the decision to adopt one land use practice over another, social and aesthetic considerations may also be important to the landowner. The relative weighting of economic, social and other factors will vary among landowners depending on the size of the farming or forestry enterprise, the level of production intensity, proximity to markets, and whether it is a full or part-time activity.
Research and Development
To advance agroforestry in the US, research is needed both on basic, process-level questions and on applied management techniques that are appropriate for commercial farm or forest operations. While basic research may, for example, investigate the long-term biological interactions between the components of an agroforestry practice, applied research should seek to maximize the tangible short and intermediate term benefits. Agroforestry practices should be tailored to readily integrate into existing farming or forestry enterprises, minimize the displacement of existing crops, use equipment and technical skills that are readily available, and allow some harvesting of products within conservation agroforestry practices (e.g., hardwood timber from riparian buffer strips). There is the potential to expand the participation of state, community and junior colleges, through their agriculture and forestry programs, in agroforestry research.
The greatest research need is to develop farm-level analyses of the potential economic costs, benefits, and risks associated with agroforestry practices. This information is a vital prerequisite to the objective comparison of both production-and conservation-driven agroforestry practices with alternative land use options. Furthermore, attention should be given to evaluations of future price trends in regional, national and international markets for commodities that can be produced using agroforestry (e.g., hardwood lumber or high-value, wind-sensitive crops). Research on tree-crop-animal-environment interactions should be pursued to provide a scientific basis for optimizing agroforestry designs.
Information and Technology Development
Technical information must be developed locally or regionally for application within that region. Information which is too general or which is based on studies conducted in dissimilar regions or climate zones is not likely to convince landowners to adopt agroforestry practices, or provide relevant skills and knowledge to ensure their success. on-farm demonstrations and field days are key to the understanding and appreciation of agroforestry practices by landowners. Education and training in agroforestry are needed both for natural resource professionals and college students.
In addition to the traditional model for the transfer of technology from researcher to extension agent to practitioner, landowners should have greater involvement in all phases of this process. With the assistance of research and extension personnel, local groups of landowners may analyze their own needs for agroforestry development, conduct on-farm experiments under real-life conditions, and then choose the practices most appropriate for their individual properties. Rather than accusing landowners of causing environmental degradation, they should be approached from a "win-win" perspective. Emphasis should be placed on participatory decision-making including landowner advisory groups. Research and information development should focus on agroforestry practices that afford economic opportunities, increase production efficiency, and provide cost-effective and pro-active solutions to conservation problems.
Public Policy
Public policy at the national and state levels impacts private land use decisions, including the adoption and use of agroforestry. Whether intentional or not, federal or state regulations may discourage landowners from adopting agroforestry practices for fear of loss of agricultural transfer payments, or government-imposed restrictions on their farming or forestry operation. Likewise, forest practice laws and regulations in some states may prohibit animal grazing. Government regulations which negatively impact agroforestry should be reviewed. Agroforestry can be a useful tool in developing voluntary and flexible approaches that enable landowners to comply with environmental quality guidelines.
Federal and, where available, state cost-share funding is perhaps the most important incentive for the adoption of farm conservation practices, including protective forms of agroforestry. It is vital to maintain and if possible expand the availability of public cost-share funding for conservation agroforestry practices. Financial incentives should be combined with flexible guidelines for the management of conservation practices by landowners. For example, riparian buffer strips can protect surface waterways by filtering sediment, chemicals and nutrients from cropland runoff, but most of their benefits will accrue downstream of the landowner who pays for their establishment. Allowing periodic harvest by coppicing trees (e.g., poplar) in riparian buffers not only provides a return to the landowner, but also is necessary for maintaining the optimal filtration capacity of the buffer.
Conclusions
The future advancement of agroforestry in the US must proceed at the state, regional and national levels. The principal focus of activity should be at the state or regional level where agroforestry groups (e.g., the Minnesota Agroforestry Coalition) help to coordinate research and outreach activities among universities, government agencies, private groups, and practitioners. At the national level, groups such as AFTA can help increase communication among researchers, extension advisors and regional agroforestry groups. Federal programs such as the National Agroforestry Center should continue to support research, disseminate information to resource professionals, and import overseas agroforestry techniques which may be adaptable to the US.
II. BACKGROUND, PURPOSE AND ACKNOWLEDGEMENTS
This national report seeks to build upon two previous documents on temperate agroforestry in the US published by the Association for Temperate Agroforestry (AFTA). In February 1994, AFTA published the report of a committee assembled to assess the potential for agroforestry in the US as part of the Resource Conservation Act appraisal for the USDA Natural Resources Conservation Service1. The document defined five temperate agroforestry practices, examined the potential acreage for agroforestry in the US, discussed the ecological and economic benefits of agroforestry, described federal support available for agroforestry, and made recommendations on how to advance agroforestry on a national level. Later that year, AFTA published the report of a workshop held in Nebraska City, Nebraska2. That report made specific recommendations related to public policy, interagency cooperation, establishment of a national agroforestry center, and funding needs for research and development.
This national report by AFTA is a synthesis of nine regional assessments of the status of agroforestry that were prepared for the USDA National Agroforestry Center (see Figure 1). The authors of each regional assessment compiled the following information: (1) description (general climate, soils and land capability); (2) environmental problems which agroforestry may help mitigate; (3) sustainability concerns; (4) status of agroforestry practices; (5) needs and opportunities for agroforestry; and (6) specific recommendations on actions to advance agroforestry. The regional reports were prepared by agency or academic authors and are based on literature reviews, personal observations, and in some cases, opinion surveys of resource professionals and practitioners. Some of the assessments were presented at the Agroforestry and Sustainable Systems Symposium held in 19943.
The definition of agroforestry, a summary of the key components that distinguish agroforestry from other farm tree planting practices, and an overview of the five main types of temperate agroforestry practices and their current status in the US appear in Section III.
The findings of the regional assessment authors were then consolidated in a national overview of issues, needs and recommendations related to agroforestry (Section IV). The purpose of the synthesis is (1) to identify common problems and needs across regions, and (2) to help prioritize efforts at the national and regional levels to address the needs for agroforestry research, development and technical information.
The major findings from the agroforestry assessments are summarized by region in Section V. All of the authors identified socioeconomic as well as environmental factors affecting future sustainability; these are combined in the "Sustainability Issues" section. The authors discussed the current status of agroforestry practices as implemented in their region. They also cited other uses of trees on farms which are not complete agroforestry practices; these are not included in the regional summaries. Factors affecting landowner willingness to adopt agroforestry practices were mentioned by most authors and are reported in the regional summaries. Identified needs, opportunities and recommendations are divided into five general categories to facilitate comparisons among regions: (1) research and development, (2) economics and marketing, (3) policy and funding, (4) education and training, and (5) information and technology development.
AFTA wishes to express its gratitude to the National Agroforestry Center for providing editorial and production assistance, and to the following reviewers who provided valuable comments during the preparation of this report: H.E. ‘Gene' Garrett, Bill Rietveld, Bruce Wight, Michael Gold, Joe Colletti, Catalino Blanche, Louise Buck, Deborah Hill, and Peter Williams. AFTA also wishes to acknowledge the outstanding work of the regional assessment authors in preparing comprehensive and insightful reviews of the status of agroforestry, and for reviewing the summaries of their assessments prepared for this report. Copies of the complete text of the regional assessments may be obtained from the USDA National Agroforestry Center (East Campus-UNL, Lincoln, NE 68583-0822).
III. AGROFORESTRY CONCEPTS AND PRACTICES
Agroforestry is an intensive land management system that optimizes the benefits from the biological interactions created when trees and/or shrubs are deliberately combined with crops and/ or animals4.
The benefits created by agroforestry practices are both economic and environmental. Agroforestry can increase farm profitability in several ways: (1) the total output per unit area of tree/ crop/livestock combinations is greater than any single component alone, (2) crops and livestock protected from the damaging effects of wind are more productive, and (3) new products add to the financial diversity and flexibility of the farming enterprise. Agroforestry helps to conserve and protect natural resources by, for example, mitigating non-point source pollution, controlling soil erosion, and creating wildlife habitat. The benefits of agroforestry add up to a substantial improvement of the economic and resource sustainability of agriculture.
Key Traits of Agroforestry Practices
Agroforestry practices are intentional combinations of trees with crops and/or livestock which involve intensive management of the interactions between the components as an integrated agro- ecosystem. These four key characteristics - intentional, intensive, interactive and integrated - are the essence of agroforestry and are what distinguish it from other farming or forestry practices. To be called agroforestry, a land use practice must satisfy all of the following four criteria:
Intentional: Combinations of trees, crops and/or animals are intentionally designed and managed as a whole unit, rather than as individual elements which may occur in close proximity but are controlled separately.
Intensive: Agroforestry practices are intensively managed to maintain their productive and protective functions, and often involve annual operations such as cultivation, fertilization and irrigation.
Interactive: Agroforestry management seeks to actively manipulate the biological and physical interactions between the tree, crop and animal components. The goal is to enhance the production of more than one harvestable component at a time, while also providing conservation benefits such as non-point source water pollution control or wildlife habitat.
Integrated: The tree, crop and/or animal components are structurally and functionally combined into a single, integrated management unit. Integration may be horizontal or vertical, and above- or below-ground. Such integration utilizes more of the productive capacity of the land and helps to balance economic production with resource conservation.
Current Status of Agroforestry Practices
A wide range of agroforestry combinations may be grouped into five basic types of practices: (1) alley cropping, (2) windbreaks, (3) riparian buffer strips, (4) silvopasture, and (5) forest farming. The characteristics of each practice and their current status of development in the US are discussed below.
Alley Cropping: This practice combines trees, planted in single or grouped rows, with agricultural or horticultural crops which are cultivated in the wide alleys between the tree rows. High-value hardwoods such as oak, walnut, and ash are typically grown in alley cropping combinations. Annual crops (e.g., row crops, forages and vegetables) cultivated between rows of nut or fruit trees (e.g., black walnut) provide extra income before the trees come into bearing and early in the long-term timber rotation. Depending on tree spacing, Christmas tree plantations may be interplanted with annual crops. Alternatively, short rotation woody crops or Christmas trees may be interplanted within plantations of longer-rotation timber trees.
Alley cropping or intercropping of tree plantations and orchards is common only in the Pacific Islands, but is also practiced in the Midwest and somewhat in the Southwest, South and Northeast.
Windbreaks: Windbreaks are planted and managed as part of a crop or livestock operation to enhance crop production, protect livestock, and control soil erosion. Field windbreaks are used to protect a variety of wind-sensitive row, tree and vine crops, to control wind erosion, and to provide other benefits such as improved bee pollination of crops and wildlife habitat. Feedlot windbreaks help reduce animal mortality, feed and water consumption, and odor. Windbreaks can function as living snow fences to help with water management by dispersing snow more evenly across cropland. A special type of multi-row windbreak ("timberbelt") is managed both to protect crops or livestock on a continuous basis, and to produce timber or biomass.
Windbreaks are most prominent in the Great Plains, although they are used in every part of the country. The Northeast is the only region where windbreaks are generally declining in importance. Feedlot windbreaks are particularly important in the Great Plains, Northwest, and Intermountain regions.
Riparian Buffer Strips: Riparian buffers consist of strips of perennial vegetation (tree/ shrub/grass) planted between cropland or pastures and streams, lakes, wetlands, ponds, or drainage ditches. They are managed to reduce runoff and non-point source pollution from agricultural activities on adjacent lands by trapping sediment, filtering excess nutrients, and degrading pesticides. They can also stabilize streambanks, protect floodplains, enhance aquatic and terrestrial habitat, improve landscape appearance, provide harvestable products, and function as a windbreak in some situations.
Interest in riparian buffer strips (also known as filter strips, riparian forest buffers and vegetative buffer strips) is growing in all areas of the US, particularly the Northeast, Midwest and Northwest. However, not all riparian areas currently without woody vegetation are actually in need of tree and shrub planting (e.g., in the Northern Great Plains).
Silvopasture: This practice combines trees with forage (pasture or hay) and livestock production. The overstory tree component provides shade and wind shelter, thereby protecting livestock from temperature stresses. In plantations of softwood or hardwood trees managed for timber or Christmas trees, grazing provides a source of income during the early years of the rotation. Some nut (e.g., black walnut) and fruit orchards may also be grazed to produce income before the trees begin bearing. Silvopasture is different from traditional forest or range management because it is intentionally created and intensively managed.
Silvopasture is important in the South and is also found in the Midwest. In the Northeast, some woodlots and orchards incorporate rotational grazing with dairy sheep or fallow deer.
Forest Farming: This practice utilizes a forested area for producing specialty crops which are sold for medicinal, ornamental or culinary uses. Shade tolerant crops such as ginseng, decorative ferns or shiitake mushrooms are intensively cultivated under a forest cover that has been modified to provide the correct level of shade. Suitable understory crops are those that grow naturally under forest conditions, or are adaptable to the edaphic and microclimatic conditions of the site. Forest farming can provide annual/regular income either before, or as an alternative to, harvesting the trees for wood products.
Forest farming is rapidly gaining interest and economic importance in all regions of the US, except the Great Plains and Intermountain.
Tropical Agroforestry Practices in the US
Two traditional, tropical agroforestry practices are unique, within the US and its territories, to the Pacific Islands. Shifting cultivation, or swidden, has been practiced since the earliest island settlers and can be sustainable provided the fallow period is sufficiently long.
Multilayer forest gardens are another common tropical agroforestry practice in the Pacific. They combine a permanent overstory of tall trees, a lower canopy of fruit and multipurpose trees, and an understory of shrubs and herbaceous plants to produce a variety of products for subsistence and sale.
Agroforestry and Farm Management
The implementation of agroforestry allows landowners much flexibility to design land management practices that satisfy their individual objectives and planning horizons. Emphasis may be placed either on production or conservation goals, although agroforestry practices combine elements of both. Because agroforestry practices are a continuum between agriculture and forestry, landowners can manage them to maximize the production of interplanted crops, animal forage or trees. Agroforestry may be used only during a limited time period as part of farm or forestry management (e.g., to generate income from grazing during the early years of a long-rotation tree plantation), or as a long-term sustainable farming system.
Farm management (or whole farm) planning is an important first step to incorporating agroforestry practices in a farming or forestry enterprise. Agroforestry involves managing trees on a long-term basis (e.g., for timber or windbreaks); therefore they need to be planted in the right place the first time. Farm management planning usually entails several phases, including (1) setting business and personal goals, (2) evaluation of the farm's existing natural features, improvements, crops produced, and financial condition, (3) identification of additional or alternative farm enterprises, and (4) determination of priorities for implementation. The planning process helps to identify which agroforestry practices have the greatest potential economic and conservation benefit for a particular property, and where they can be implemented to complement, rather than compete with, other farming practices.
Practices Which Are Not Agroforestry
A variety of other practices currently used in the US may appear to be agroforestry, but do not meet all four of the basic criteria for agroforestry practices. Either they are not deliberately planned and intensively managed, or they do not involve integrated combinations of trees, crops and/or animals whose interactions are consciously manipulated and enhanced. In no way does such a distinction imply that these practices are less viable than agroforestry; it is only intended to more clearly delineate the functional boundaries of agroforestry in the US. Some examples of practices which are not agroforestry are listed below.
Forest and Orchard Grazing: Livestock grazing of native forests and plantations is practiced in all regions of the US. However, it is often opportunistic, rather than part of a deliberate, intensive effort to produce both animals and trees (e.g., when cattle or sheep are used simply to clear brush before trees are planted). In open rangeland, trees may be incidental to, and not an active part of, livestock management. Fruit orchards may also be grazed intermittently for weed control, but unless combined livestock and fruit production is intended, this practice is not agroforestry.
Farmstead Windbreaks: Windbreak buildings improve living conditions of rural dwellers by reducing heating costs, dust, and noise. In areas with harsh winters, trees are planted specifically to protect rural roads from blowing snow and thereby reduce snow removal costs. However, they are not considered agroforestry since, unlike field or feedlot windbreaks, they are not an integrated part of agricultural production.
Special Forest Products: Gathering of naturally-occurring special forest products from forestland is increasing in many areas of the US. Special forest products include, for example, wild medicinal plants, craft materials, floral greens, and wild mushrooms. In contrast, forest farming involves the planting and intensive cultivation of specialty understory crops in a manipulated forest environment.
Farm Woodlots: Farm woodlots are planted or native stands of trees managed for a variety of wood (e.g., fuelwood, timber, posts, and poles) and non-wood (e.g., honey) products. Fast-growing hardwoods have been established in large, single species plantations which are intensively managed for pulpwood or biomass fuel. However, when these practices do not actively incorporate crop or livestock production, they are not considered agroforestry.
Table 1. Characteristics of temperate agroforestry practices that have current or potential importance in the US*
| Agroforestry Practice | Practitioner's Goals | Design and Management Criteria | Time
Horizon |
Regional importance |
| Field
Windbreaks |
Farmer: increased income from better crop yield & quality; soil erosion control | minimize crop displacement, maximize area of wind protection, fast-growing trees, seasonality of problem winds, reduce tree competition with crop for water & nutrients | multi-year | all
(less so NE) |
| Livestock
Windbreaks |
Rancher: increased production & reduced mortality of livestock | minimize width, maximize amount of wind reduction, fast-growing trees, seasonality of problem winds, control impact of animals on tree growth & survival | multi-year | NW, NGP, SGP |
| Silvopasture: tree emphasis | Forest Landowner: extra/early income from livestock production; weed control | close-spacing of trees, maximize tree growth, tree protection needed, thinning & pruning of trees for wood quality, forest management to promote understory forage, control impact of animals on tree growth & survival | early in tree rotation | PI, SGP, MW, S |
| Silvopasture: animal emphasis | Rancher: increase animal production with shade, shelter and fodder from trees, extra income from timber | maintain pasture & fodder tree growth, thinning & pruning of trees for pasture growth, fodder yield & palatability, wide spacing of tree rows, manage shading & root competition that reduces pasture growth | annual & multi-year | PI, SGP, MW, S |
| Alley Cropping: tree emphasis | Forest Landowner: extra/early income from interplanted crops; weed control | close tree spacing, intercropping only during early years, reduce competition of crops with trees for water & nutrients | early in tree rotation | PI, SW, MW, S, NE |
| Alley Cropping: crop emphasis | Farmer: extra income from long-term timber crop | wide spacing of tree rows, maintain crops longer in rotation, tree thinning & pruning to increase crop growth & wood quality | annual & multi-year | PI, SW, MW, S, NE |
| Riparian
Buffers |
Farmer: reduce NPS pollution and sediment (compliance); fee hunting from game species | minimum displacement of crops, minimum width for buffering effectiveness, crop &/or tree harvesting within buffer, cost of fencing to exclude livestock, loss of grazing land | multi-year | NGP, SW, NW, MW, NE |
| Forest Farming | Forest Landowner: extra/early income from cultivated understory crops | thinning or clearing of trees to enhance understory crop cultivation; intensive management | annual & multi-year | PI, SW, NW, MW, S, NE |
*Regional abbreviations: IM-Intermountain, MW-Midwest, NE-Northeast, NGP-Northern Great Plains, NW-Northwest, PI-Pacific Islands, S -South, SGP-Southern Great Plains, SW-Southwest.
IV. ISSUES, NEEDS AND RECOMMENDATIONS
Based on the environmental diversity reflected in the regional assessments, it is clear that one or more agroforestry practices can be implemented anywhere within the continental US and its Pacific island territories. Climate, soils, and land capability do not pose absolute restrictions on tree and shrub planting. Within each region, locally adapted species and appropriate establishment techniques are used for agroforestry plantings.
Nevertheless, climatic and edaphic conditions are important limiting factors on tree establishment in some regions (e.g., Intermountain, Northern and Southern Great Plains). In some areas within those regions, the choice of species is more restricted due to harsh environmental conditions. Not only is the need for protective plantings such as windbreaks greater in these areas, but the cost to establish trees and shrubs also will be higher than in locations where milder environmental conditions prevail.
Because of the extra costs associated with irrigation, alley cropping and silvopasture may be more economically viable in areas of the US that normally receive sufficient rainfall to support both trees and crops together. However, the availability of low-cost water (e.g., municipal or industrial wastewater) for irrigation may make these practices possible in drier climate zones.
Riparian buffer strips can be established along any stream or river with sufficient soil moisture to support perennial woody vegetation. Even in areas affected by brackish water or saline soil, adaptable species can be identified for buffer plantings.
Forest farming can be practiced wherever there is sufficient forest cover, and edaphic and climatic conditions are suitable, for the cultivation of shade-tolerant understory crops. Higher rainfall areas of the country are likely to be more suitable for forest farming compared to regions with low rainfall and high potential evapotranspiration. However, high crop values can offset irrigation costs.
Natural Resource and Environment
Four natural resource sustainability issues were cited as being critical in every region of the US: soil erosion, water quality, wildlife habitat, and riparian zones. All areas of the US are subject to soil erosion by water or wind, and erosion control is one of the primary reasons for conservation agroforestry practices. The quality of both surface and ground water resources is a major issue in all regions. The primary concern is non-point source pollution, i.e., sediment, nutrients, chemicals and animal wastes, resulting from agriculture, industry, and communities. The loss of biodiversity and declining populations of bird, animal, and fish species resulting from terrestrial and aquatic habitat destruction is an issue nationwide. A major contributing factor in the degradation of water quality and loss of wildlife habitat throughout the nation is the clearing of vegetation from riparian areas.
Several other environmental problems cited in the assessments have regional significance. Concerns about the impacts of farming operations on air quality (e.g., dust, soil particulates, and odor) are important in the Southwest, Northern and Southern Great Plains, and Midwest. Also in the Midwest, issues related to the reclamation of surface coal minelands and regeneration of native hardwood species are important. Other regional problems include the impacts of farming on natural playa lakes in the Southern Great Plains, the spread of invasive non-native plants in the Southwest, and the decline of aquifers used for irrigation and drinking water supplies in the Southern Great Plains.
Socioeconomic
Four socioeconomic issues are of nationwide importance: urban encroachment on rural areas, farm demographics, declining rural economies, and public land management. In all regions, except the Great Plains and the Pacific, the expansion of cities into rural areas is occurring at a rapid pace. This "urbanization" process creates both challenges and opportunities for farming, ranching and forestry. A national trend in farm demographics is changing the priorities for agroforestry research and technology development: fewer, but larger farms account for a high proportion of total agricultural production, while the number of small, part-time, or "lifestyle" farms is growing. At the same time, the strength of rural, resource-based economies has weakened, particularly in parts of the West dependent on timber harvests from public lands. This has resulted in part from conflicts over the management of public lands, which has a proportionally greater impact in regions where large acreages are publicly owned.
Several other socioeconomic issues affecting sustainability mentioned by authors of the regional assessments also have national relevance. Health problems of native populations resulting from dietary changes is a concern in the Pacific Islands and the Southwest. The economic impacts of geographic isolation and the transition from subsistence to market-based economies are major issues facing the Pacific Islands. Farmworker health and food safety were important issues mentioned in several regions. The cost and availability of energy was cited as a concern in two regions (Intermountain, Southern Great Plains), although it also affects every region of the country. Likewise, although the impact of the global economy and NAFTA on agriculture was mentioned only in one region (Intermountain), this of course has national relevance.
If agroforestry practices have such promising economic, environmental and social benefits, why are they not practiced more widely today in the US? Many of the authors of the regional assessments cited a variety of factors which affect the adoption of agroforestry practices by private landowners. Some have regional significance, while others are valid considerations throughout the US. An understanding of both the motivations for, and constraints against, adoption of particular land use practices is necessary to better tailor research and education programs.
A general observation mentioned by several authors is that most private landowners are not familiar with the term "agroforestry," although they may recognize land use practices that fall within the definition (e.g., windbreaks or riparian buffer strips). Extension advisors and other land use professionals are more likely to have heard the term "agroforestry," although they tend to associate it with a particular land use practice in their region rather than as a suite of different practices. In some cases, landowners or professionals associate agroforestry with practices which are controversial or which they actively discourage (e.g., uncontrolled forest grazing). Lack of recognition of the general term "agroforestry" by practitioners may not necessarily be a cause for concern since technical and financial assistance programs would more likely focus on specific agroforestry practices (e.g., alley cropping). Whether or not a particular land use practice is seen by the landowner as "agroforestry," a number of factors affect their willingness to adopt that practice.
An important element of landowner adoption cited by some of the regional assessment authors pertains to the size and commercial intensity of farms. Owners of large, "industrial" farms, small sustainable/organic farms, and part-time or hobby farms each have a different set of priorities for land management. Larger farming operators are more likely to be concerned primarily with short-term profit potential while small farming operators may be more interested in environmental or aesthetic benefits which do not necessarily generate cash returns. Therefore, different agroforestry practices may appeal, for different reasons, to these distinct groups of landowners.
Reasons for Adoption
Economic gain was cited as the most important reason why landowners may adopt an agroforestry practice. Opportunities to profitably produce a marketable product through production-driven agroforestry, to generate income during the early years of a long-term tree rotation, and to diversify farm income with supplemental products are all primary motivating factors.
Government incentive programs to reduce out-of-pocket costs for the establishment of some conservation-oriented agroforestry practices are a major reason for their adoption. The importance of government assistance varies by region and by program. For example, federal cost-share programs are used in almost one-half of all tree planting on non-industrial private forestland in the South, while relatively little agroforestry planting has resulted from public cost-share funding in the Northeast. Some states also provide cost-share incentives for particular agroforestry practices.
The need to mitigate an environmental problem (e.g., damaging winds) is another important reason for agroforestry adoption. The underlying motivation may be to increase income by improving the conditions for plant or animal growth, or it may be for the sake of conserving a vital resource (e.g., erodible soil). As a corollary to environmental mitigation, the fear of government regulation, which imposes restrictions on land use, may motivate some landowners to adopt them pro-actively.
For some landowners, although certainly not most, the principal reasons for adopting an agroforestry practice may be non-economic. Land uses which provide aesthetic, recreational, environmental and/or domestic use benefits are attractive, particularly to landowners who do not need to earn their entire living from the land.
Constraints to Adoption
Counter balancing the positive reasons that landowners adopt agroforestry practices are a number of negative factors which may discourage adoption. The constraints mentioned in the regional assessments may be categorized within four broad categories: economic, land management, information and technology development, and public policy.
Just as economic factors may be the main reasons for a landowner's decision to use an agroforestry practice, they may be paramount considerations in the decision not to use agroforestry. Other alternative land uses may offer more potential profit with a shorter waiting period and with less risk in established markets than do production oriented agroforestry practices. Reliable farm-level cost/benefit analyses are often lacking for agroforestry. Capital for start-up and operating costs for new or untested practices may be difficult to obtain. The perceived high cost of establishment of agroforestry practices was mentioned by several authors as the over-riding constraint to adoption (e.g., extra irrigation costs necessary to establish trees in a harsh environment). The lack of, or restrictions on, government cost-share funding is an important disincentive for conservation agroforestry.
Agroforestry adoption may also be constrained by factors related to land management. Trees and shrubs may be seen to interfere with farming operations (e.g., aerial spraying or equipment movement), to compete excessively with crops for limited resources (e.g., water), or to displace valuable cropland. on-farm trials of agroforestry practices may yield disappointing results or prove incompatible with existing cropping patterns, which dissuades the landowner from larger-scale adoption. Land tenure is also an issue because tenant farmers are not likely to be able to invest in practices that take a long time to yield economic or other benefits. Other alternative practices (e.g., residue management or crop rotation) may be seen as more effective than tree planting in improving agricultural productivity and sustainability.
The lack of practical, locally-relevant information on the economics and management of agroforestry practices often discourages their adoption. Without printed information, agroforestry-literate extension advice, on-farm demonstrations, or experience of other local farmers, many landowners are not convinced that agroforestry is a proven land use option. Agroforestry practices may require unfamiliar management skills, additional labor, or customized services which are not locally available. There may be conflicting or erratic promotion of agroforestry among and within public agencies. With the exception of some growers' associations that produce specialty crops, there is no well-organized, grass roots support or beneficiary group which promotes agroforestry on behalf of its farmer-members, as do many commodity-centered farm associations and marketing cooperatives.
Public policy may directly or indirectly affect rural land use, and some policies contain disincentives to agroforestry adoption. For example, forest practice regulations or taxation policies may discourage forest grazing. The current Conservation Reserve Program restricts active management of planted hardwoods, thereby eliminating agroforestry as an option. Rural landowners are also at a disadvantage regarding legislation affecting them due to the concentration of political power in urban areas. As one author noted, institutional policies may discourage long-term interdisciplinary research on innovative agroforestry practices.
The regional assessments identified a variety of needs and opportunities to advance agroforestry research and development. Some needs were voiced by several authors, while others pertain primarily to individual regions. Many general and specific recommendations for action were also proposed. General recommendations are integrated in the following summary of needs and opportunities (refer to the summaries of the individual regional assessments in Section V for more specific recommendations).
Research and Development
There was a unanimous call by the authors for more research on agroforestry. To help overcome the information gap in agroforestry, research should be regional and site-specific so that landowners do not have to rely on results from other, dissimilar regions. Both applied and basic research are needed, especially programs that extend across a geographic region to show where and under what circumstances particular agroforestry practices are likely to succeed. Given the nature of agroforestry, research needs to be long-term and interdisciplinary. Because the objectives of large corporate farms and small family farms may be different, approaches to research should accommodate those differences. In the Pacific Islands, research is needed that integrates traditional, subsistence agroforestry practices with modern, market-driven practices.
Among specific topics for research, the greatest need is for research which quantifies the direct and indirect economic costs, benefits, and risks of agroforestry practices for specific regions and applications. Research is needed on ways that landowners can realize some income from land devoted to conservation-oriented agroforestry. For example, cropping or selective harvesting of trees within riparian buffers may be compatible with maintaining the filtering capability of the buffer strip. Research is needed on low-cost, fast-growing windbreaks that displace a minimum amount of cropland but still provide adequate shelter.
For silvopasture, additional livestock management research is needed on techniques to reduce the impact of trampling and browsing on trees and soils. For alley cropping, research is needed to select crop species which are complementary to the trees, and on crop cultural practices that reduce injuries to tree roots or trunks (i.e., which may degrade wood quality). The selection and improvement of plant materials for agroforestry requires long-term work, but is critical to maximizing the potential for economic gain from agroforestry.
Economics and Marketing
Because economic considerations are often the most important consideration leading to landowner adoption of agroforestry practices, most authors placed a high priority on farm-level financial and economic studies. Similar to the budgets routinely prepared by extension economists for the production of field and orchard crops, real data are needed on the expected costs and returns from production-driven agroforestry practices. More attention should be given to the development of domestic and export markets for agroforestry products, and marketing intermediaries between producers and consumers (e.g., marketing associations representing growers of forest farming products).
For conservation-oriented agroforestry practices, many authors recommended a more thorough accounting of the value of "externalities" of agroforestry practices (e.g., the economic, environmental and social benefits associated with the amelioration of non-point source pollution). These non-product benefits of agroforestry need to be quantified, such as lowering heating and cooling costs, reducing airborne dust and fine particulates from wind-erodible farmland, maintaining water quality, and enhancing wildlife habitat. This information would allow farm managers to evaluate the trade-offs between on-farm practices and off-farm effects, and could encourage adoption of some agroforestry practices. It would also help policy makers determine who should pay for, and who gains from, the benefits of conservation practices implemented on private lands.
Education and Training
All regional assessments identified a need for training of extension, agency, and technical personnel so they will better understand the potential benefits, costs, and limitations of agroforestry practices, and know under what circumstances to recommend them to landowners. Cooperation among agencies in training workshops is an important element in coordinated efforts aimed toward the goal of increasing landowner adoption. one author suggested that training in sales techniques is needed for extension advisors. College-level course curricula should be developed which covers both theoretical and applied, region-specific aspects of agroforestry.
Information and Technology Development
Coupled with the currently inadequate state of technical assistance in agroforestry, the regional assessments identified the need for quantitative information on agroforestry practices that is regionally and locally relevant. Guides to agroforestry information sources, resource packets for libraries and extension offices, and computerized "expert" systems would benefit both landowners and public agency advisors. Beyond printed information, a powerful tool for conveying technical information is on-farm demonstration sites. Most authors placed a high priority on the development of applied agroforestry demonstrations that can be utilized for field days and seminars. Technology development is aided by "turn-key" custom services (e.g., tree planting) that private entrepreneurs or conservation districts provide for landowners.
Most authors expressed the need to improve communication about agroforestry with farmers, foresters, ranchers and other groups. Many landowners are unfamiliar with the term "agroforestry," and factual information is needed to counter negative perceptions associated with particular practices. Where concrete data are lacking, the authors cautioned that the potential benefits of agroforestry should not be oversold. Partnerships with stakeholder organizations can improve communication about agroforestry and coordinate joint efforts behind informational or demonstration projects. Information on suitable agroforestry practices should also be directed toward suburban homeowners (e.g., home or subdivision shelterbelts), and native American tribes (e.g., tree crops for dietary improvement). The rural/urban interface is an ideal location to demonstrate the benefits of agroforestry.
Public Policy and Funding
Public land use policies and the availability of financial incentives can either be a major contributor or deterrent to the adoption of agroforestry. Government regulations and taxation policies that discourage agroforestry need to be examined (e.g., restrictions on income from timber crops on lands enrolled in CRP). Several authors stressed the importance of federal leadership for agroforestry development through the National Agroforestry Center, specifically including an ecosystem- based approach to land management, coordination of contact points for landowner assistance among different agencies, and establishment of regional research programs. Most authors identified cost-share funding, mainly from federal but also from some state programs, as a critical factor in the establishment of conservation types of agroforestry. However, concern was expressed over the future availability of government cost-share funds for agroforestry, given the current federal budget reallocations. A need was identified for targeted funding to support long-term, interdisciplinary research at land grant universities, and to finance regional small grants programs for agroforestry demonstration and marketing projects.
V. SUMMARIES OF REGIONAL ASSESSMENTS
Region Description
For this report, the Northeast region includes the New England states of Maine, Vermont, Massachusetts, New Hampshire, Connecticut and Rhode Island; the mid-Atlantic states of New York, Pennsylvania, and New Jersey; and the south-Atlantic states of Delaware, Maryland, Virginia and West Virginia (see Figure 1). The assessment focused on one representative state within each sub-region; Vermont, New York and Maryland.
The region has a continental climate with relatively homogeneous temperature gradients and no markedly dry season. Some soils are not productive for annual crops, but do support trees. Land use in the Northeast is mainly forest (60%), cropland (13%), pasture (8%) and urban (11%).
Sustainability Issues
Environmental
Erosion: Soil erosion and sedimentation are important non-point sources of water pollution from agriculture. Cropland erosion is declining due to a combination of improved practices and loss of land in agriculture. The amount of cropland considered highly erodible is also declining.
Water quality: The health of water resources is a prime concern. Agriculture is a major source of sediments, pesticides and nutrients affecting water resources. Rural septic systems are also an important source of pollutants.
Wetlands: There is growing concern over the loss of wetlands that provide fish and wildlife habitat and water quality functions.
Riparian buffers: Some 66,000 lineal miles of riparian streambank in the region are without trees or shrubs. Clearing of riparian vegetation has caused streambank destabilization and erosion.
Socioeconomic
Farm demographics: Total farmland acreage has decreased in all states, due to the general decline of the agriculture industry in the region. In some areas, agricultural lands are being rapidly converted to metropolitan uses, while in others abandoned agricultural lands are reverting to their former forested status. From 1980-93, average farm size in the region increased and the number of farmers decreased, except in Massachusetts and Vermont where the total number of farms increased.
Suburbanization: The region is more urbanized than the nation as a whole. Development is also increasing in rural areas. However, urbanization creates opportunities for low-volume, high value production for specialty markets in urban and suburban areas. A characteristic urban-rural fringe agriculture is emerging based on local production and consumption strategies and dense market networks.
Forestry: Most Northeastern forestland is owned by small private landowners. Amenity values as well as timber potential are important to them. Development pressures on rural lands provide a strong incentive to forest landowners to harvest and then sell their land for development.
Agroforestry Practices
Historical: Native peoples in the Northeast practiced nut tree planting, gathering, and shifting cultivation. Woodlots and forest grazing were common practices among the early European settlers. Today, each of the five main agroforestry practices is evident, but most are practiced on a limited, spontaneous basis.
Alley Cropping and Intercropping: High value hardwoods for timber may be interplanted with "nurse tree crops" (e.g., black locust), or herb or forage crops during the early years of establishment. Examples are evident of organic fruit and vegetable production within alleys between rows of nut or willow trees. Such operations are small scale and their products destined for local farmers markets. Interplanting of small fruits in orchards or vineyards is not widespread, but has been practiced for many years.
Forest farming: Markets for high value specialty products (e.g., ginseng, maple syrup, and mushrooms) are growing. Development is aided by both marketing and growers associations (e.g., the Vermont Specialty Foods Association, New York State Ginseng Association). Among the five practices this probably has the greatest potential for significant expansion in the region.
Riparian buffers: While riparian buffers have been established on only a very limited basis to date, interest in their economic and environmental value is rapidly expanding. Several states in the region have active riparian buffer programs.
Silvopasture: Intensive rotational grazing schemes sometimes incorporate the use of woodlots and abandoned orchards on a carefully controlled basis.
Windbreaks: Windbreaks and shelterbelts are generally in a state of decline in the region as landowners continue to invest in their removal. There is some evidence they are being developed or rehabilitated to protect vineyards and alternative livestock operations (e.g., fallow deer, sheep.)
Landowner Adoption
Perceptions of Agroforestry
The authors conducted a survey of 42 resource professionals and landowners regarding the status and potential of agroforestry in the Northeast. They found that while most landowners are not familiar with the term "agroforestry", most resource professionals are. Most resource professional tend to associate agroforestry with a particular application or practice, some of which they may actively discourage (e.g., forest grazing).
Agroforestry is not a widely known or used concept in the Northeast, though interest is growing. It assumes various meanings within different geographic and land use contexts. In Appalachia and New England agroforestry tends to be equated with forest farming, while on the Coastal Plains the term more commonly refers to riparian buffer strips. Most agroforestry practices have arisen spontaneously from demographic and market forces that shape land use patterns. Relatively little agroforestry implementation results from public cost-share funding or technical assistance programs.
Public support for agroforestry
Federal: Although federal cost share programs include some agroforestry practices (e.g., CRP, ACP, SIP), the acreage of land on which these practices have been implemented using federal cost-share is small.
State: Several state and watershed-level water quality programs support riparian buffer plantings (e.g., the Chesapeake Bay Program, Connecticut River Joint Commission).
Needs/Opportunities/Recommendations
Research & Development
Urban-rural interface: Dense networks of mixed urban and rural land uses create the need for "environmentally-friendly" buffering between the two. Strategies for making these protective plantings as productive and profitable as possible should be investigated. The production of willow and poplar for energy biomass presents one under-exploited opportunity.
Understory cultivation: Better information is needed about the site conditions required for cultivating high quality herbs in the forest understory on a continuous basis. The potential complementarity between maple syrup and herb production enterprises in parts of Appalachia and New England should be investigated.
Watershed protection: Roles of riparian buffers and forest farming in watershed and wetland protection should be carefully investigated, and public incentive programs to landowners tailored accordingly.
Abandoned land conversion: Silvicultural and economic dimensions of managing the succession of abandoned agricultural land to advance the production of high value timber with low intensity haying or grazing need to be better and more widely understood.
Specialty products: Community supported agriculture and farmer's markets provide opportunities for marketing of agroforestry specialty products. While these products have long been sold in the region, it has been on a small scale and limited basis. The domestic and international market potential for woods-grown products of many varieties needs to be more systematically monitored.
Information & Technology Development
Potential: There is significant unmet potential to expand agroforestry knowledge and practice in the region.
Networking: Efforts to coordinate and focus the expanding interest in agroforestry (e.g., the Northeast Agroforestry Consortium) will need at least a minimal level of public financial resources.
Policy & Funding
Tenure and taxes: Important disincentives to the practice of agroforestry fall within the realm of tenure and tax policy. The development of cooperative agreements through collaborative problem-solving among public agency and private interests concerned with sustainability issues can help address such constraints on a pilot, demonstration basis. In this context, agroforestry may be more readily viewed as a strategic bridge between conservation and development objectives throughout the region.
Small grants: There is need for a regional small grants program focused on agroforestry technology, marketing and policy reform needs, modeled partially after the Sustainable Agriculture Research and Education Program (SARE). Unlike the current program, it must provide for multi-year findings and outcomes.
Cost-share: Federal cost share and associated technical assistance programs should be coordinated and reoriented to support integrative approaches to land use.
Leadership: National leadership and financial resources aimed toward sustainable land use practices are needed to advance agroforestry in the region.
Region Description
The South includes the following ten states: Alabama, Arkansas, Florida, Georgia, Kentucky, Louisiana, Mississippi, North Carolina, South Carolina and Tennessee (see Figure 1). The region has a generally moderate climate with year-around precipitation and relatively long growing seasons. Some soils in the region have limitations due to low fertility, shallowness and water logging.
Most of the undeveloped non-federal land is in forest (57%), 22% is cropland, and 14% is pasture. From 1982-87, over two million acres of crop and pasture lands were lost to development. There is a high potential for conversion of land- use between forestry and agriculture. The region's large forest land base is highly productive; over 80% of Southern forest land is capable of growing at least 50 cubic feet of industrial wood per acre annually. Private ownership predominates, with about 70% of commercial timberland owned by non-industrial private landowners.
Sustainability Issues
Environmental
Soil erosion: Erosion exceeds the national average in 8 of 10 states in the region. Nutrient runoff problems are exacerbated when farmers try to compensate for fertility loss by adding fertilizer. Exposed subsoils often contain toxic elements (e.g., aluminum). Wind erosion problems are local and relatively modest.
Water quality: Non-point source pollution of surface and groundwater from agricultural irrigation activities (e.g., pesticides, nitrates and sediment runoff) is a problem in 8 of 10 states.
Riparian zones: Clearing of riparian zones for farming has increased runoff and sedimentation.
Wildlife: Land-use changes (e.g., agricultural development, forest clearing and urban growth) have contributed to species endangerment.
Socioeconomic
Growth: The region's population is growing more rapidly and is more rural than the nation as a whole. It lags behind the nation in terms of disposable income, poverty reduction and educational attainment.
Farm demographics: Average farm size in the South is smaller than the national average. From 1990-93, the number of southern farms decreased by about 4% while average farm size increased slightly.
Agroforestry Practices
Historical: The earliest form of southern agroforestry was forest grazing. However, the practice became controversial due to land use conflicts and problems caused by uncontrolled grazing.
Silvopasture: Native forest grazing is the dominant agroforestry practice in the region, mainly loblolly pine-grass-cattle combinations. The South has the greatest potential acreage for forest grazing in the US. Animals other than cattle are used to a lesser extent (e.g., sheep for forest brush control). While some financial evaluations of silvopasture are encouraging, the negative effects of grazing and trampling on seedling survival and soil productivity remain a major concern.
Combination of grazing with pecans is intensively practiced in areas where pecan orchards are established (e.g., Louisiana). Although pecan trees are mainly grown for nuts, overmature trees are being harvested for furniture-grade lumber.
Intercropping/Tree-crop and tree-forage: These practices are not as common as forest grazing. Crops such as soybeans or grains are cultivated in plantations of fast-growing hardwoods (e.g., cottonwood or sycamore) early in the rotation.
Landowner Adoption
Survey of public land-use professionals
Reasons for adoption: The most frequently mentioned reasons for adopting agroforestry practices are (in rank order): (1) economic gain, (2) multiple land use management and income diversification, (3) site suitability and erosion control, (4) shortening the wait for and increasing the regularity of income, and (5) consistency with environmental and ecological concerns.
Constraints to adoption: The most commonly noted problems associated with agroforestry practices are (in rank order): (1) negative effects of livestock on seedling survival and soil productivity, (2) low productivity or poor economic performance, (3) lack of management skills and technical knowledge, (4) incompatibility between the multiple outputs, and (5) high establishment and annual management costs.
Additional factors affecting landowner adoption
Cost-share: one or more federal forestry cost-share programs were used in 47% of all tree planting on non-industrial private forestland (1993). Agroforestry was adopted on only 1.2% of the total Stewardship Incentive Program acreage from 1991-95, although there was a sharp increase in agroforestry enrollments during 1994-95. While federal programs predominate, some states (i.e., Mississippi and North Carolina) also provide incentives for tree planting.
Site potential: Land use professionals (survey respondents) placed more emphasis on site potential than the innovativeness or technical knowledge of the landowner when selecting situations most appropriate for agroforestry implementation. Silvopasture was recommended by 70% of respondents while 30% recommended tree-crops.
Non-economic values: Results of another recent survey of private forest landowners suggest that opportunities exist for agroforestry practices that provide non-economic benefits (e.g., aesthetic, recreational, environmental and domestic use) at a reasonable cost.
Needs/Opportunities/Recommendations
Research & Development
Research priorities: Southern land use professionals identified the following critical research needs for agroforestry (in rank order): (1) improvement of economic returns, (2) enhancing productivity, (3) reducing damage to trees and soils by livestock and farm equipment, (4) quantifying the potential of agroforestry to solve environmental problems, including wildlife impacts, and (5) educating the public and extension personnel about agroforestry.
Marginal lands: Almost 17 million acres of marginal crop and pasture lands in the South could produce higher economic returns if planted to pine. Pine and hardwood tree-crop and tree-forage combinations would generate regular cash flows and encourage the establishment of tree cover on highly erodible lands. The soil fertility of marginal lands could be enhanced with legume cover crops or nitrogen fixing trees.
Riparian buffers: Re-establishment of woody vegetation in riparian areas could improve water quality and provide timber production and wildlife habitat. By selectively harvesting timber and maintaining riparian forests in an active growth phase, the buffer's pollution amelioration potential is more fully realized.
Windbreaks and natural barriers: Although not as common as in other regions, windbreaks are needed to protect sandy soils in areas subject to wind erosion (e.g., Southern Mississippi Valley Alluvium, Coastal Plain soils). Windbreaks also protect sensitive crops (e.g., tobacco) from sand abrasion. Windbreaks would improve the efficiency of poultry and pork operations by reducing climatic stresses, and also provide wildlife habitat.
Natural pine management: Livestock grazing can improve the financial returns from natural pine forest management, and thus could affect the current trend towards conversion of native pine forests to plantations after harvest. The availability of shade tolerant forage species is critically important. Pine straw mulch is another potential source of revenue from natural pine forest.
Hardwood plantation-crops: Removal of southern hardwoods is exceeding growth. Intercropping early in the rotation and direct seeding could help offset the relatively high regeneration costs. Black walnut intercropping should be considered on abandoned cropland and riparian areas. Increasing stumpage prices for southern hardwoods help to offset the higher establishment costs for hardwood plantations. Production of fast-growing hardwoods like paulownia may become economically feasible if markets develop.
Pine plantation-crops: Harvesting of softwood timber also exceeds growth in the region. Interplanting a crop early in the rotation would improve cash flow.
Specialty products: Production of specialty products is likely to be important for small landowners involved in organic and/or environmentally sensitive types of farming and weekend hobbyists. Suitable niche products include honey, mushrooms, honeylocust, and ginseng.
Education & Training
Training: Southern land-use professionals listed the following needs for improving the capacity of extension personnel in agroforestry (in rank order): (1) distribution of guidelines for recommending livestock and forestry combinations, (2) availability of economic and productivity data, (3) training on how to develop demonstration sites, (4) distributing guidelines for mixing crop and forest management, and (5) distributing guidelines for enhancing wildlife management.
Information & Technology Development
Extension: Land-use professionals suggested the following recommendations for improving agroforestry extension (in rank order): (1) expanded training of extension personnel, (2) development of a research base and evaluation guidelines, (3) expanded publicity, (4) development of demonstration sites, (5) improved inter-agency cooperation, and (6) increased numbers of personnel specialized in agroforestry.
Policy & Funding
Cost share: Current federal cost share programs don't always allow for agroforestry practices. Moreover, given current federal budget problems, it appears likely that federal cost-share programs will be reduced or eliminated in the future.
Recommended actions: In the absence of traditional federal cost-share programs to encourage agroforestry, these actions are recommended: (1) lobby for state and regional cost-share programs for agroforestry, including funds for programs involving urban forestry, waste management, and recreation/tourism, (2) initiate demonstration, research and development projects to educate land use professionals and owners about the potentials of agroforestry, and (3) expand funding for economic and social research to document the potential profitability of agroforestry practices beyond their environmental benefits. Landowners need to be assured that agroforestry will produce at least an equal or greater return than alternate land use investments. Reducing financial uncertainty is the "single most important factor" for encouraging agroforestry adoption.
Region Description
The Midwest region encompasses the states of Minnesota, Wisconsin, Michigan, Ohio, Indiana, Illinois, Iowa and Missouri (see Figure 1). The region has a continental climate with temperature extremes and year-around rainfall. Most of the soils are highly productive for agriculture and forestry. The landscape of the Midwest is dominated by agriculture and remaining native hardwood forests.
Sustainability Issues
Environmental
Erosion: Loss of soil from agricultural operations is the principal environmental problem of the Midwest.
Water quality: Non-point source pollution from agriculture impacts water quality (e.g., sediment, nutrients, pesticides, and animal wastes).
Air quality: Problems include dust and odor from feedlots, compounded by the lack of windbreak protection.
Loss of wildlife habitat: Clearing of native woody vegetation has reduced bird and animal populations.
Riparian devegetation: The clearing and cultivation of riparian corridors has contributed to wildlife habitat loss and water quality degradation.
Surface coal mining: Reclamation of mined lands is a slow and costly process, and failures lead to surface water pollution and erosion problems.
Hardwood forests: Regeneration of fine hardwoods is not keeping pace with harvesting. Regionally-adapted practices that can meet the high demand for hardwoods are needed.
Socioeconomic
Growth: Continued urban/suburban expansion into rural areas and the conversion of forests to agriculture and urban development has prompted state land use regulations (e.g., "Right to Farm" ordinances) and proposals for similar rules to protect rights to practice forestry. Urban growth has also inflated rural land prices.
Rural economy: In the eastern portion of the Midwest, there has been a shift from an agrarian to an industrial economy. In Ohio, less than 10% of the population is involved in farming, while in Iowa more than 25% are involved in farming. Regional farm income is relatively strong, although the number of people in farming is generally decreasing and average farm size increasing due to consolidation.
Agroforestry Practices
Historical: Early settlers in the Midwest practiced slash and burn agriculture and tended multi-layer home gardens.
Intercropping: Among agroforestry practitioners, agrisilviculture (e.g., alley cropping) is among the most common, followed by mixed systems outside of alley cropping [intercropping], and Christmas trees combined with crops.
Black walnut: Agroforestry management of black walnut for timber, nuts and grazing is gaining interest. The involvement of a commercial company in Missouri (Hammons Products Co.) has played an important role in information and demonstration related to black walnut agroforestry.
Silvopasture: Grazing of sheep and cattle in native hardwood forests and black walnut plantations is common among agroforestry practitioners.
Windbreaks: Windbreaks and boundary plantings are also common among agroforestry practitioners.
Landowner Adoption
Needs identified by field-level professionals and practitioners
Water quality: Major problems result from both agricultural practices and suburbanization. Research is needed on the minimum width required for an effective buffer along streams, since streambanks and ditches can be the most productive soils for crop planting.
Landowner education: Farmers and the public need to be made aware of non-point source pollution problems (e.g., from feedlots and lawn fertilization).
Soil erosion: Research is needed on improved windbreak designs that are inexpensive, fast-growing and take up as little space as possible.
Rural development: Opportunities for agroforestry adoption are presented by new, small landowners willing to use incentive programs and their own funds to try alternate land uses that do not provide immediate financial benefits.
Training: Training of professionals is needed on the use of agroforestry to enhance biodiversity.
Cost-sharing: Stewardship and incentive programs are important to agroforestry adoption; reauthorization of the Farm Bill will influence what takes place on the ground. In Missouri, cost- share funding is available for alley cropping through the state Department of Conservation.
Reasons for Adoption
Motivation: It appears that adoption of agroforestry is motivated primarily by income potential and/or aesthetic or hobby reasons. Conservation plays a minor role in adoption except for landowners wishing to promote wildlife.
Farm size: A survey of agroforestry practitioners indicated that the majority of agroforestry in the Midwest is being implemented on small tracts where annual income from farming operations may be of lesser importance.
Constraints to Adoption
Policy: Although state programs exist to promote farm tree planting (e.g., windbreaks), restrictions apply which limit their use for other types of agroforestry. The Classified Forest Act (Indiana) provides tax relief to forest landowners, but excludes lands that are grazed.
Cost/benefit data: There is a lack of reliable farm-level cost/benefit data for agroforestry practices in the region. Economic analyses need to internalize the social and environmental benefits and to account for markets and labor availability.
Land tenure: Where the average length of land ownership has decreased in recent decades, long term investment in agroforestry is less feasible.
Political power: The rural population is at a disadvantage regarding legislation that affects rural programs due to the greater political power of urban centers.
Needs/Opportunities/Recommendations
Research & Development
Biological process research: There is a lack of fundamental research that extends across the region to show where and when agroforestry practices are biologically and economically effective and where they are not. Current research does not allow applied or basic comparisons among soil types, climate zones, crop mixes, or whole agroforestry systems.
Erosion control: Agroforestry practices can play a major role in the reduction of soil loss (e.g., windbreaks, alley cropping, and riparian buffers).
Wildlife: Agroforestry can contribute to wildlife conservation by creating habitat through the planting of hedgerows, windbreaks, and riparian buffers.
Minelands: Mining reclamation with a mix of grass, crops and trees would provide quick cover and erosion control as well as long term habitat and income.
Specialty Products: Growing specialty products or developing artificial agroecosystems to support recreational activities (e.g., fee hunting) may be part of the forestry enterprise.
Fine hardwoods: Agroforestry with black walnut and other hardwoods can help encourage planting to meet the strong market demand by offsetting initial plantation establishment costs.
Waste application: Research is underway in Iowa on applying municipal sludge to woody energy crops in alley cropping.
Biomass and pulp: Agroforestry with fast growing trees (e.g., hybrid poplar) could play an important role in supplying biomass for energy production and paper pulp.
Economics & Marketing
Economic data: A limiting factor for implementation is case-study economic data that landowners can use for decision-making.
Information & Technology Development
Promotion: Agroforestry in the Midwest is still young, and therefore the potential of agroforestry practices (e.g., alley cropping) should not be oversold. Its promotion should progress with "healthy skepticism."
Information: The lack of data on biological and economic potentials of agroforestry practices across the region precludes providing proven options to landowners. Most landowners will not be convinced by the inadequate information base for agroforestry that is currently available.
Region Description
The Northern Great Plains includes the states of Montana, Wyoming, North Dakota, South Dakota and Nebraska (see Figure 1). The region's semi-arid climate is characterized by low and variable rainfall, temperature extremes, high potential evapotranspiration, periodic drought, and strong winds. Some soil types present conditions difficult for tree establishment (e.g., heavy texture, alkalinity), particularly in areas of rigorous climate.
Most tree planting has occurred on land capability class III or better soils; tree planting is unsuitable on class VII-VIII soils and poorly suited on class VI soils. Major tree planting efforts in the region date from the Prairie States Forestry Project in 1935.
Sustainability Issues
Environmental
Farm practices: Conventional agricultural practices, such as clean cultivation, stream-side grazing, cropping border to border, chemical use, and cultivation of highly erodible land, are causing "significant damage" to natural resources.
Soil erosion: Wind erosion accounts for 60-70% of gross cropland erosion in the region. Water erosion above tolerable levels occurs on 10% of regional cropland. The off-site costs of erosion (e.g., sedimentation)may be as significant to society as losses in crop yields.
Water quality: Non-point source pollution from agriculture impacts both surface and ground water in the region. Sedimentation severely affects waterways, reservoirs and canals, and also riparian and fisheries habitats.
Air quality: Air quality is periodically impaired by agricultural operations. While the impacts can be severe for short periods, they are not long-lasting.
Socioeconomic
Economy: Agriculture has the greatest promise for future improvement in the region's economy, but there is the need to better protect natural resources. Recreation, tourism and industrial development are other important components of regional economic sustainability.
Agroforestry Practices
Farm tree plantings in the Northern Great Plains are primarily for conservation and protection: 30% are field windbreaks, 38% are farmstead/feedlot windbreaks, 29% are wildlife plantings, and 3% are for other purposes (e.g., living snowfence, Christmas trees, etc.).
Windbreaks: Reducing soil loss is the most commonly accepted reason for tree planting in the region. However, 50% of current windbreak plantings are functioning below their potential and need renovation.
Riparian buffers: No states in the region have significant plantings of artificially established woody buffer strips, but interest appears to be growing.
Intercropping: No operational examples were found.
Landowner Adoption
Future trends in US agriculture: Like elsewhere in the US, agriculture is undergoing dramatic changes in the region, and the trend is towards "mass-industrialization." Modern agriculture is more specialized, labor efficient and capital intensive than the diversified, non-intensive agriculture of 60 years ago for which windbreaks were originally designed. About 50,000 large farms, franchises and co-ops will be responsible for 90% of commercial production in the US by next century, and the remainder of the agricultural sector will comprise about 1.5 million small, part-time and hobby farms.
Different approaches to the development of sustainable practices are required for large industrial farms and small family farms. While emphasis on agroforestry's multiple benefits may serve well for smaller farmers, larger farmers are likely to be more interested in short-term economics. Therefore, the potential for agroforestry to have significant impact depends on the structure of the agriculture community in the future.
Agriculture must adopt environmentally-sound practices to achieve long-term sustainability while also maintaining productivity. The threat of government regulation may compel adoption of new practices. Nevertheless, a survey of agency staff suggested that crop diversification, residue management and crop rotation would be more effective than tree planting in improving agricultural productivity and sustainability in the region.
Constraints to Adoption
Cost: Due to harsh climate and soil conditions, tree establishment is difficult and therefore costly. High cost and difficulty are also impediments to windbreak renovation.
Interference: Interference with and from agricultural operations constrains tree planting (e.g., herbicide use in small grains production).
Markets: There is a lack of reliable markets for farm-grown wood products in the region. Production of market-based agroforestry products is unlikely due to geographic dispersal, lack of strong market demand, and difficult tree growing conditions.
Conventional wisdom: Many landowners believe that the costs associated with windbreaks exceed their potential benefits. Also, many believe that residue management alone is sufficient for erosion control.
Promotion: There is erratic promotion and/or discouragement of agroforestry among and within public agencies.
Needs/Opportunities/Recommendations
Research & Development
Sustainability: Research should address the most important sustainability issues for cultivated cropland: erosion, salinity, and water quality.
Windbreaks: The highest priority is research and development leading to the renovation or replacement of field windbreaks, focusing on their economic benefits. Energy conservation with farmstead/feedlot windbreaks is a high priority for research.
Riparian buffers: Riparian restoration and buffer planting are also high priorities.
Other practices: Improvement of wildlife habitat and living snowfences are important in the region. However, other agroforestry practices (e.g., fuelwood, alley cropping, and silvopasture) are likely to have limited potential in the region.
Education & Training
Training: There is a need for resource managers and technical advisors who are knowledgeable in agroforestry. Salesmanship training is also important.
Information & Technology Development
Promotion: "Realizing significant gains in the incorporation of trees and shrubs on agricultural land would require very aggressive and extended promotion."
Target audience: The primary target audience for agroforestry information are landowners and producer groups. Landowner initiative and contact with other landowners are important factors in decision making.
Services: Tree establishment and maintenance "turn key" services by Conservation Districts and individual entrepreneurs, and the increased use of weed-barrier fabrics in drier regions, would facilitate tree planting on farmland.
Demonstration: More demonstration projects (e.g., North Dakota's "Project Renovate") and windbreak education are needed.
Policy & Funding
Cost-share: Tax incentives and cost-share are the most important means to reduce establishment and maintenance costs. Increased cost-share funding would provide the greatest opportunities for agroforestry expansion.
Agency coordination: Public agencies should coordinate among themselves to agree on which agroforestry practices are most needed.
Region Description
The Southern Great Plains includes the states of Kansas, Oklahoma and Texas (see Figure 1). Moisture and heat stress due to the semi-arid climate in much of the region are limiting factors on plant growth. Most of the soils have good agroforestry potential. About 40% of all non-federal land is crop or pasture land, 51% is range and 7% is forest.
Sustainability Issues
Environmental
Water quality: Non-point source pollution from farmland, pasture and feedlots impacts surface water quality.
Groundwater: Contamination of drinking water supplies by nitrate and pesticides is a concern. Irrigation pumping has significantly lowered water tables, leading inevitably to the reduction in irrigated acreage and a return to dryland farming on many lands.
Erosion: Wind erosion is severe on 12 million acres in the region, and annual rates are higher than the national average.
Air quality: Dust, spray drift, and odor from agricultural operations, particularly large feedlots, impact air quality.
Riparian zones: Irrigation diversions, stream channelization, over-grazing, and land clearing have severely affected riparian areas.
Playa lakes: Farming impacts on playa lakes (which dry up in summer) include devegetation from grazing and clearing, loss of wildlife habitat from disking and burning, feedlot runoff, and increased sedimentation and organic nutrients.
Wildlife and Fisheries: Intensification of agriculture in the region has reduced wildlife and fish habitat. Restoration of riparian zones and playa lakes could be the best means of improving wildlife habitat.
Socioeconomic
Sustainability issues: Agricultural sustainability concerns in the region include: (1) creating healthy local economies that withstand climatic extremes and economic boom/bust cycles, (2) ensuring continued soil productivity on cropland enrolled in CRP, (3) farmworker health, (4) food safety, (5) energy cost and availability, and (6) declining groundwater aquifers.
Agroforestry Practices
Windbreaks: Windbreaks are commonly used in the region to protect soil, crops and livestock. Plantings of field windbreaks decreased from 1982-87. There is substantial potential to use feedlot windbreaks for livestock protection.
Riparian buffers: While incipient riparian management may be occurring, there are few concrete examples of deliberate riparian restoration or agroforestry practice in the region. The best example of coordinated efforts at wetland and riparian management is the Wetlands and Riparian Areas Project (WRAP) in Kansas.
Intercropping: There is no evidence found of intercropping in the Southern Great Plains.
Landowner Adoption
In the region, "there is little purposeful agroforestry in which tree and agricultural components are deliberately managed together." The only common agroforestry practices are windbreaks and cattle grazing with trees.
Constraints to Adoption
Lack of quantitative agroforestry research: Research is needed on many topics, including genetics, site adaptation, and economics.
Externalities: There is a need for research to analyze the economic, environmental and social costs, and the thresholds of erosion, non-point source pollution, and other environmental consequences of agriculture. This research would allow farm managers to evaluate trade-offs between on-farm practices and off-farm effects, and thus may lead to increased adoption of agroforestry.
Lack of institutional structures: Being interdisciplinary, agroforestry in the US lacks established institutional structures to support needed research and development. Technical advisors do not have adequate knowledge to assist producers with the implementation of agroforestry practices.
Lack of public understanding of agroforestry: Public awareness of agroforestry was found to be very low within the region.
Needs/Opportunities/Recommendations
Research & Development
Highly erodible cropland: There is substantial potential to use agroforestry practices such as windbreaks and intercropping to protect highly erodible land.
Riparian buffers: Riparian vegetative buffer strips are the "highest priority need." An important research topic is the design of agroforestry practices in the riparian zone that optimize crop mixes while maintaining adequate buffering capacity.
Grazing: Grazing is important in the region and the potential to increase grazing of forests, red cedar, pecan, and fodder trees should be studied.
Intercropping: Research is needed to document the potential benefits of intercropping.
Economics & Marketing
Marketing: Marketing frameworks that provide intermediaries between agroforestry producers and consumers may facilitate access to larger markets.
Education & Training
Extension: Training for extension personnel is needed so they will recognize the potential of agroforestry practices and be able to provide technical assistance to landowners.
Information & Technology Development
Information: "Significant adoption of agroforestry practices will not occur until additional quantitative information and demonstration sites are available and economic incentives change. This will require both substantial public investment and fundamental reforms in academic institutions and government agencies."
Policy & Funding
Institutional: Overcoming the constraints to adoption of agroforestry requires: (1) earmarked funds for research, (2) revitalized leadership infrastructure, and (3) modified public agency perspectives.
Policy: Incentives must be provided to landowners for them to reasonably consider agroforestry. Allowing for income opportunities on CRP lands while meeting erosion control requirements would protect more acres in the long-term.
The Intermountain region includes Colorado, Idaho, Nevada and Utah (see Figure 1). The climate is highly variable and strongly influenced by elevation. Arid lowlands support shrub and grass vegetation while rainfall at higher elevations is sufficient to support dense forests.
Sustainability Issues
Environmental
Water cost and availability: While most water is now used for agriculture, increasing demand for residential and in-stream (e.g., fish and wildlife) uses could lead to restricted supplies and higher costs for irrigation.
Loss of biological resources: Habitat destruction resulting from traditional land uses and urban growth have threatened fish and animal species.
Energy: Energy conservation continues to be a long-term concern for the region.
Socioeconomic
Growth: The region's population is highly urbanized and rapidly growing. The Intermountain states are among the top six fastest growing states in the nation. Growth is rapidly altering the region's economy and established land uses.
Farm economy: There has been a decline both in the number of farms and per-acre values from 1985-92.
Declining natural resource-based industries: Prices of agricultural and mineral commodities have declined (1975-88), seriously impacting rural economies. Although timber prices have increased over the same period, supplies from national forests in the region have dropped dramatically and there is only a limited amount of private timber land that can realize the potential gains from higher stumpage prices.
Demographic changes: Rapid urban growth, declining resource-based economies and limited rural employment opportunities, have fueled urban migration and eroded the stability of rural communities. Urban/wildland interface issues have become more critical.
Global economy: NAFTA and global trade will affect the profitability of new and existing land uses, which in turn will affect rural economies and demographics.
Agroforestry Practices
Windbreaks: Windbreaks are the only common agroforestry practice in the region, and they are extensively used only in Colorado. The Field Windbreak Campaign has actively promoted windbreak planting in Colorado. The Idaho Agroforestry Coalition involves public agencies and private groups to promote agroforestry practices.
Other practices: Other agroforestry practices that are less common in the region include field windbreaks, living snowfences, and riparian buffers.
Landowner Adoption
Constraints to Adoption
Economic: The restricted availability of capital and limited agroforestry markets, services and supplies for agroforestry affect its adoption in the region.
Environmental: Harsh environmental conditions for tree establishment in the Intermountain region increase the costs of tree establishment (e.g., irrigation requirement).
Needs/Opportunities/Recommendations
Research & Development
Priorities: An assessment by NRCS foresters concluded that all states could benefit from more field windbreaks. In all states except Utah, the establishment of riparian buffers is a priority. Living snowfences are a priority for Colorado and Idaho, farmstead windbreaks are priorities in Nevada and Utah, and Christmas trees are recommended for Utah.
Goals: The region needs agroforestry practices that (1) provide economic opportunity in rural areas (e.g., Christmas trees, specialty products); (2) enhance energy efficiency and the livability of human environments (e.g., residential windbreaks); and (3) improve water quality and wildlife habitat (e.g., riparian buffers).
Tribal lands: Characterized by marginal productivity, high unemployment, and subsistence use, tribal lands need windbreaks and multipurpose trees.
Urban/Suburban: Agencies should expand their programs to embrace this non-traditional, yet politically powerful constituency. one way would be to encourage residential windbreaks for energy conservation, aesthetics and wildlife.
Site-specific: Research from other regions has limited application to the Intermountain states. Therefore, research should be specific to the region's conditions and needs (e.g., windbreak design and effects on crops). Suitable species for agroforestry in the region need to be identified.
Economics & Marketing
Rural economic opportunities: Opportunities exist to increase markets for Christmas trees, specialty products, and trees for production landscaping.
Education & Training
Training: Educational opportunities should be expanded in three critical areas: (1) training for extension, agency and technical personnel; (2) training opportunities for landowners; and (3) agroforestry college courses at the region's Land Grant universities. Improved employment opportunities in agroforestry are needed to continue university programs.
Information & Technology Development
Demonstration: Demonstration sites are needed to foster awareness and improve region-specific technical information.
Policy & Funding
Coordination: Better coordination between agencies, universities and the private sector is needed. Working partnerships between government and the private sector are needed to establish demonstrations and create new markets and services.
Incentive programs: Existing federal cost-share programs (e.g., SIP and ACP) should be expanded. Funding programs for water quality could be used to encourage establishment of riparian buffers and shelterbelts. Land trusts and conservation easements could also be used to promote agroforestry.
Federal leadership: The region's large federal land ownership makes federal leadership important in the adoption of agroforestry practices. Ecosystem management should be viewed as an opportunity to expand agroforestry.
Region Description
The Pacific Northwest, which includes (for this report) northern California, Oregon and Washington, is a region of dramatic physical and environmental contrasts (see Figure 1). The principal north-south mountain ranges divide two distinct climate zones: the western coastal portion with higher rainfall and more even, moderate temperatures, and the drier and colder eastern interior. The region contains highly productive forest, range and farmland.
Sustainability Issues
Environmental
Soil erosion: Farmland erosion is a serious regional problem. Although water erosion in Oregon and Washington decreased from 1982-92, the rates are still above the national average. Wind erosion in Washington during that period increased, counter to the national trend. Erosion of range and riparian areas is due to over stocking and poor management. Forestland erosion is the result of logging road construction, recreational use, fire, and timber harvesting.
Water quality: Runoff of sediment, nutrients, and chemicals from farmland leads to pollution of surface waters. Improper use of household chemicals and septic systems on rural/suburban acreages should not be overlooked.
Riparian degradation: Riparian areas in the region are subject to flooding and erosion, both inherently and through human activity. Devegetation of riparian areas harms fish and impoverishes habitat for other animals.
Fish and Wildlife: Fragmentation and loss of wildlife habitat on farm, range and forestlands are affecting fish and wildlife populations, particularly migratory species.
Socioeconomic
Growth: Rapid population growth is creating intense pressure for the development of forest, farm and rangelands.
Public lands: A high percentage of land in the region is publicly owned. There are conflicting views, from diverse groups, on desirable objectives for public land management. Decisions on the management of public lands also affect private landowners and rural dwellers (e.g., reduced harvesting of federal timberland and proposed changes in grazing of public land).
Rural economy: Rural communities are severely impacted by declining timber harvests and changing agricultural economics, resulting in reduced educational opportunities and social services.
Agroforestry Practices
Silvopasture: Combined timber and pasture production is still rare in the Northwest, but it has "excellent prospects" based on the early results of trials in western Oregon.
Windbreaks: Windbreaks are sometimes used to protect crops and livestock in the region. More may be planted by new rural dwellers seeking privacy, beauty and energy conservation. Many of the older windbreaks have deteriorated or been removed. Interest in wildlife may help spur more windbreak planting.
Riparian buffers: "Of all agroforestry practices, woody riparian buffers is the one with the greatest future importance due to the extraordinary economic and environmental costs of not improving the region's watersheds." Caution should be used in extrapolating recommendations for riparian buffers from other regions.
Landowner Adoption
Constraints to Adoption
Obstacles to adoption include the high cost of establishment, insufficient financing and lack of technical assistance.
Needs/Opportunities/Recommendations
Priorities to advance agroforestry in the Northwest include better coordination among multiple contact points for technical assistance, training for technical assistance personnel, clarifying financial assistance options, and improving the research base.
Research & Development
Site-specific: Research on agroforestry practices must be regional and site specific. Commercial trial plantings to demonstrate ecological and economic performance are needed.
Economics & Marketing
Economics: Develop real data on costs and returns for marketable products from agroforestry practices. Market development for new agroforestry products is often neglected.
Externalities: It is difficult to identify the external (e.g., environmental) cost savings of agroforestry and to fairly allocate these savings between those who pay and those who gain.
Opportunity cost: It is important to weigh the establishment and management costs of proactive agroforestry practices (e.g., riparian restoration, erosion control) against the costs of not doing so.
Information & Technology Development
Information: There is inadequate technical assistance on agroforestry in the region, largely because the relevant research base is weak and demonstration sites are lacking.
Planning: The objectives of an agroforestry practice must be made explicit as it is designed, implemented and evaluated. Knowledge limits must be recognized and the potential benefits not over-sold if agroforestry is to become more accepted.
Ecosystem management: While the goals of ecosystem management are admirable, they will be difficult to implement. Small-scale, short-term actions are needed to incrementally improve ecosystem sustainability "while learning to think, plan and act on broader geographic and temporal scales."
Policy & Funding
Funding: Private funding for agroforestry research is scarce when there is no direct commercial interest involved. Since agroforestry lacks a well-organized beneficiary group, it does not fare well in competition for funding with other worthy land-use research needs.
Region Description
For the purpose of this assessment, the Southwest region includes southern and central California, Arizona and New Mexico (see Figure 1). The region's climate is generally semi-arid, with variable rainfall and temperature regimes. Arizona and New Mexico receive some rainfall year-round while California receives rain only in winter. The better soils are devoted to agriculture, although soil-related problems such as salinity and waterlogging limit their capacity for tree growth.
Highly productive irrigated farmland is found in California and Arizona, and the mountains of all three states support extensive native forestland. All three have large federal ownerships of timberland, and tribal lands are important in Arizona and New Mexico.
Sustainability Options
Environmental
Soil erosion: Water erosion has resulted from poor grazing, logging and development practices. Some areas are subject to wind erosion.
Water quality and availability: Fertilizer and pesticide application in farming areas has contaminated ground and surface waters. In several areas of irrigated farmland, inappropriate water management has led to salinization and water-logging of the soil. The availability of surface and ground water has been altered by pumping for irrigation, damming, stream channelization and invasive phreatophytic weeds.
Air quality: Dust generated from abandoned or fallowed farmland without windbreaks leads to health problems and highway accidents in all three states. In desert areas, blowing sand creates a physical problem encroaching on highways, housing and farmland.
Wildlife habitat: Little undisturbed habitat, including wetlands, riparian zones and old growth forest, remain in the Southwest. While attention has focused on individual rare and endangered species, ecosystem protection may be essential for species protection.
Non-native plants: Competitive, invasive weedy species of Mediterranean origin have a negative impact both on agriculture and native plant communities.
Pest management: Monocultural crop systems are more vulnerable to pests than complex systems.
Socioeconomic
Development: In the Southwest, land is rapidly being converted to urban and suburban uses. Development of 5 to 20 acre ranchettes are fragmenting many areas of farm, range and timberlands.
Public health: Diabetes is endemic in the Native American communities of the Southwest as a result of dietary changes. Fine particulates and fungal spores in blowing dust lead to lung disease and Valley Fever disease.
Economics: The marginal economics of rural resource management have led to the conversion of forestlands to brush and the abandonment of cropland. Poverty is a severe problem in many rural areas.
Agroforestry Practices
Historical: The native peoples of the Southwest were skillful "applied ecologists" who planted and tended trees for food and other needs. The early settlement period was characterized by rapid resource extraction.
Windbreaks: Field windbreaks are common, and are still being planted to protect high value row, vine and tree crops. Windbreaks are also used to shelter highway and railroad lines from blowing sand.
Intercropping: one commercial example of intercropping is dates interplanted with citrus in the Coachella Valley of California.
Riparian buffer strips: The planting of riparian filter strips has not been widely adopted or promoted in the Southwest. However, riparian and wetlands restoration projects are underway in Arizona and California.
Landowner Adoption
Constraints to Adoption
Economics: "Farmers are reluctant to adopt agroforestry practices until their profitability is demonstrated."
Emphasis on technical rather that socio/political issues: Land tenure, a hopeful view of the future, and absence of crippling farm debt are necessary ingredients for successful agroforestry development. The importance of women in resource management is often overlooked.
Subsidies and distorted markets: "Economic considerations are the most critical factor in the adoption of agroforestry and sustainable resource management. People can rarely be encouraged to do something that is ‘right' if it is not also economically advantageous." Accounting for external costs, i.e., environmental degradation, will be a key to agroforestry development. Tax, regulatory and institutional policies may discourage the adoption of agroforestry practices.
Ignorance: "Simple ignorance is probably the most serious impediment to agroforestry development in the Southwest." Relevant information on agroforestry is difficult to find, and most of it is poorly indexed and distributed.
Over-specialization: The narrow focus of education and research in US academic institutions contributes to the lack of information and expertise in agroforestry. Specialization also makes it difficult to get funding for innovative research.
Separation of knowledge and experience: Basic and applied research are often separated in the US. There is a need for more "hands-on" and problem-based learning and research.
Limited time, vision and commitment: Short-term funding cycles are incompatible with agroforestry research that may take 10 or more years. Differing priorities among agencies in the US affect how well agroforestry practices are promoted. Many public agencies are crippled by funding cutbacks and hiring freezes.
Emphasis on publications: Short-term theoretical or laboratory studies are often favored over applied, long-term interdisciplinary projects. Current academic reward systems in US universities favor publications rather than achieving practical solutions to problems.
Needs/Opportunities/Recommendations
Research & Development
Wild harvest: Special forest products are the most immediate option for new job creation in the region. A wide variety of specialty products could be collected or cultivated, including mushrooms, pinyon pine nuts, berries, mesquite pods, and acorns. Traditional medicinal plants could also help reverse the incidence of diabetes in Native Americans.
Tree crops on cropland: New specialty crops could be produced for the growing Asian and Latin American markets. In California, fast growing hardwoods such as paulownia could be grown profitably. The use of wastewater to reduce irrigation water costs could be useful in establishing and maintaining agroforestry trees.
Windbreaks: Greater use of windbreaks could be expected if their economic benefits are quantified and training and extension materials are improved. Specific benefits that need study include the potential health care savings as a result of dust control, and reduced vehicle fuel use and accidents on windbreak-sheltered highways.
Ground and drainwater management: An estimated 7.5 million trees on 25,000 acres would be required for regional ground water management in central California.
Tree fodder: The use of trees for fodder (e.g., poplar, willow, and leucaena) may be less environmentally costly and more profitable than alfalfa.
Coppice crops: Coppice is promising as a means to produce fuelwood, fodder and craft materials, and to provide environmental protection in the Southwest.
Trees on range and pasture: The most important agroforestry development on rangeland is likely to be shade and shelter for livestock. Fast-growing timber trees or nut trees could be planted in pastures to serve as shelterbelts. Other research needs include living fences, native hardwoods, and economical means for the reconversion of brushlands to productive use.
Forest gardens: Research and development trials are needed to suggest urban forestry designs for energy conservation, food, medicine, etc., appropriate for low income and farmworker housing, suburban homes, parks and rural ranchettes.
Filter and buffer strips: Filter strips are needed to reduce erosion and water pollution from irrigated cropland in California and Arizona. Live cuttings (e.g., willow) could also be used along streambanks to control erosion.
Biodiversity: Windbreaks, filter strips and tree plantations will also provide needed wildlife habitat, thereby improving biodiversity.
Other research priorities: Cooperative research on agroforestry practices should be started with Native American farmers. An inventory of useful trees and agroforestry practices appropriate for the Southwest and its climatic analogs worldwide should be undertaken. Research is needed on traditional medicinal plants.
Economics & Marketing
Cost/benefit analyses: Detailed economic analyses of the costs, benefits and risks associated with agroforestry practices are needed for specific sites and applications, watersheds and regions.
Import/export: Evaluate the potential for substitution of tree crops in import/export markets for the nation, states and regions.
Policy & Funding
Ecosystem: "Approach all land management issues from an ecosystem perspective."
Regional centers: The establishment of regional agroforestry research centers and the support of partnerships with private non- governmental organizations are needed. Interagency working groups focused on agroforestry should be created.
Forest policy: Obstacles to agroforestry in forest policy and practice regulations should be reviewed and removed.
Tax and regulatory policy: There is a need to assess tax and regulatory policies that provide economic disincentives to practicing agroforestry.
Dust Buster: Review policy to determine if a Dust Buster program is needed, similar to the Swamp Buster and Sod Buster programs.
Funding: Develop funding for long-term, interdisciplinary research involving basic and applied topics.
Education & Training
Extension: Develop agroforestry extension programs for farmers, foresters, and homeowners. A key step would be to prepare a guide to sources of agroforestry information.
Education: Interdisciplinary agroforestry curricula and course materials adapted for the Southwest region are needed. Alternatives to current reward systems in academia should be investigated (i.e., that foster long-term interdisciplinary research).
Literacy requirement: Ecological and cultural literacy requirements should be developed for new academic positions, with hands-on training to improve skills.
Information & Technology Development
Demonstration: Establish regional and local agroforestry demonstration sites with regular tours, workshops, etc. Research plots with small landowners could also serve for demonstration. Large-scale demonstration projects could be developed on abandoned agriculture land.
Technical information: Develop manuals on agroforestry for specific user groups in different bioregions and climate zones. Distribute agroforestry information to libraries, including key agroforestry journals.
Expert systems: Develop a "smart system" to identify appropriate agroforestry practices and predict probable costs and profits.
Region Description
The Pacific Islands region includes the Hawaiian islands and US affiliated islands in Micronesia, Polynesia and Samoa (see Figure 1). The area has a tropical climate, characterized by high rainfall and humidity, and warm temperatures year-round. The soils are mainly of volcanic origin, and their agricultural fertility is dependent on maintaining vegetative cover and preventing erosion, particularly on steep slopes.
Sustainability Issues
Environmental
Soil erosion: Erosion is a serious problem resulting from the cultivation of crops on steep land under heavy precipitation. Erosion also results from fire and land clearing activities.
Water quality: On atoll islands, pumping for irrigation and domestic use can lower the ground water table, thereby causing salt water intrusion. on larger islands, fertilizer and pesticide runoff from farmlands have contaminated ground water.
Rare and endangered species: The Pacific Islands are home to a rich variety of endemic plants and animals. Loss of habitat through clearing for agriculture and development, along with the introduction of damaging, non-native plants and animals, threatens the indigenous biodiversity.
Socioeconomic
Health problems: Many of the native inhabitants of Pacific Islands suffer from diabetes and heart disease, largely as a result of a shift from their traditional diet to imported, processed food.
Rural economy: Some of the Pacific Islands (e.g., Micronesia and Palau) are undergoing a transition from a subsistence to a cash economy. Economic development is made more difficult by their isolation, small size and dependency on natural resources (e.g., fisheries) which have an uncertain future. Rural poverty has fueled a trend to urban migration. Farm income is often insufficient to pay for investment in conservation practices.
Agroforestry Practices
Several agroforestry practices used in the Pacific Islands are found no where else in the US. They take advantage of the tropical climate and the rich diversity of useful plants available.
Shifting cultivation: "Swidden" agriculture has been practiced since the earliest settlers. It is sustainable when the fallow period is long enough (e.g., 15-25 years) to renew soil organic matter and fertility.
Multilayer tree gardens: This common agroforestry practice typically consists of three layers: (1) a permanent overstory of trees (e.g., breadfruit, coconut, forest species), (2) a lower canopy of fruit and multipurpose trees, and (3) an understory of shrubs and herbaceous plants. It produces a variety of products both for subsistence and commercial sale.
Windbreaks: Field windbreaks are common in locations subject to persistent trade winds, and are used to protect crops, orchards and pastures.
Intercropping: In Samoa, the N-fixing legume Erythrina is interplanted in gardens and banana plots. Coffee plantations in Hawaii may be established with an intercrop of sorghum; elsewhere mature coffee is interplanted with bananas and shade trees. Taro is of great importance on many islands, and patches of taro may be intercropped between tree gardens.
Alley cropping: Alley cropping on sloping land between parallel hedgerows of nitrogen fixing trees planted on the contour is being demonstrated, but so far few landowners have adopted this practice.
Silvopasture: Local people have used plantations to graze livestock. Research in Hawaii has been conducted on using cattle, sheep and goats under macadamia, guava and banana plantations.
Landowner Adoption
Constraints to Adoption
Changing interests: on many smaller islands, there is a greater interest in modern rather than traditional lifestyles, particularly among young people. This has resulted in a declining number of young people involved in farming. Some agroforests are left unharvested and unmanaged due to the lack of available labor.
Technical simplification: The focus on short-term income from agriculture and shorter periods of average land tenure have led to shorter rotation lengths and cultivation of fewer crops at one time compared to traditional agroforestry practices. There is also a loss of indigenous knowledge of agroforestry practices as generations change.
Rural Economics: Inter-island markets for agroforestry products are hampered by isolation, high transportation costs, infrequent shipping schedules and quarantines. Smaller islands may not be able to economically compete with developing (Asian) countries in the production of export crops due to higher costs of land, labor, production and shipping, and inexperience in meeting quality standards. High-value crops are also subject to theft on some islands.
Needs/Opportunities/Recommendations
Research & Development
Integrated research: Although agricultural research in the Pacific has often been separated between "traditional" and "modern" practices, there is a need for applied research which integrates both approaches through agroforestry. Research should be aimed to serve farmers’ current needs (for cash, etc.).
Plant materials: Farmers need access to high quality planting materials of selected species and improved cultivars through local nurseries.
Economics & Marketing
Markets: Efforts should be directed to: (1) develop markets for existing agroforestry products, (2) add marketable cash crops to traditional agroforestry practices, and (3) develop high-value, lightweight, non-perishable agroforestry products for export.
Tourism: Agroforestry is a visually attractive land use and, by reducing erosion, it protects marine resources which attract tourists. Traditional farms with agroforestry can also be promoted as tourist attractions, and agroforestry products can be marketed directly to tourists.
Cattle grazing with Acacia koa: This is an economically promising land use for existing pastures, which combines grazing with high-value hardwood production. Grazing improves the early cash flow and may reduce property taxes.
Economic value: The economic values of agroforestry practices and products need to be quantified.
Education & Training
College forestry: There is a critical need for college-educated, native foresters in Samoa and Micronesia. A college degree program in forestry is being considered at the University of Hawaii.
Training: Training in agroforestry practices is needed for local extension staff, especially outside Hawaii. Also, better extension material and operations funding is required.
Information & Technology Development
Women: The traditional role of women in farming on Pacific islands should not be overlooked in extension efforts.
Extension: A forestry extension specialist at the University of Hawaii is needed to disseminate information generated by research. A national forester or agroforester for the Federated States of Micronesia is also needed.
Public education: An objective explanation of the benefits and a fairly specific definition of agroforestry are needed to overcome misunderstanding of the term "agroforestry". Enthusiasts have tended to oversell the potential benefits of agroforestry. In Hawaii, it had been identified with particular practices that are the subject of controversy (e.g., unmanaged grazing or plantation silviculture).
Diet: Public campaigns to encourage consumption of traditional agroforest foods (e.g., the "Waianae diet" in Hawaii) also promote agroforestry.
Policy & Funding
Land Tenure: The impact of land tenure on agroforestry needs examination. For example, in Hawaii, concentration of private ownership in relatively few, large holdings has limited the access of smallholders to land for long-term investment in horticulture. Property taxation also influences land use (e.g., grazing is usually taxed lower than forestry in Hawaii).
Federal funding: Grants from the USFS support operating budgets for agroforestry nurseries, training, demos and extension in Samoa and Micronesia, which makes these programs vulnerable to cut-backs.
EIS: Some islands need the establishment of environmental impact statement procedures, to help emphasize sustainability in land use and agricultural development.
1 Garrett, H.E., et al., 1994, Agroforestry: an integrated land-use management system for production and farmland conservation, Assn. for Temperate Agroforestry, 58 pp.
2 AFTA, 1994, Agroforestry for Sustainable Development: A National Strategy to Develop and Implement Agroforestry, Workshop to "Develop a Framework for a Coordinated National Agroforestry Program," June 29-30, Nebraska City, NE
3 Rietveld, W.J., Technical Coordinator, 1995, Proceedings, Agroforestry and Sustainable Systems Symposium; 1994, August 7-10, Ft. Collins, CO. General Technical Report RM-GTR-261. USDA Forest Service, Rocky Mountain Forest and Range Experiment Station, Ft. Collins, CO
4 Garrett, H.E., et al., 1994, Agroforestry: an integrated land-use management system for production and farmland conservation, Assn. for Temperate Agroforestry, 58 pp.
5 A summary of the report, Agroforestry Practice and Potential in the Northeast: a Macro-level Assessment, by Louise E. Buck and Amy B. Waterman, Dept. of Natural Resources, Fernow Hall, Cornell University, Ithaca, NY 14853-3001
6 A summary of the report, Agroforestry and Sustainable Systems in the South, by F. Christian Zinkham, Lundy-Fetterman School of Business, Campbell University, Buies Creek, NC 27506, and D. Evan Mercer, USDA Forest Service, P.O. Box 12254, Research Triangle Park, NC 27709.
7 A summary of the report, An Agroforestry Assessment of the Midwestern United States, by Andrew R. Gillespie, J. Doland Nichols and Shibu Jose, Forestry and Natural Resources Dept., 1159 Forestry Bldg., Purdue University, West Lafayette, IN 47907-1159.
8 A summary of the report, Present Status and Future Potential for Agroforestry in the Northern Great Plains, by Peter R. Schaefer and John J. Ball, Dept. of Horticulture, Forestry, Landscape and Parks, South Dakota State University, P.O. Box 2207C, Brookings, SD 57007-0096.
9 A summary of the report, Agroforestry and Sustainable Systems in the Southern Great Plains, by Steven Anderson, Forestry Dept., 008C Agricultural Hall, Oklahoma State University, Stillwater, OK 74078-0491.
10 A summary of the report, Agroforestry and Sustainable Systems in the Intermountain Region, by Robert J. Lilieholm, Dept. of Forest Resources, Utah State University, Logan, UT 84322-5215.>
Region Description
11 A summary of the report, Agroforestry Opportunities in Northern California, Oregon and Washington, by Linda H. Hardesty and Linda M. Lyon, Dept. of Natural Resource Sciences, Washington State University, Pullman, WA 99164-6410.
12 A summary of the report, Agroforestry in the Southwest: A Rich Past and Promising Future, by David A. Bainbridge, Biology Dept., California State University, San Diego, CA 92182.
13 A summary of the report, Agroforestry in the United States-Affiliated Pacific Islands: Present Status and Future Potential, by Kathleen S. Friday, USDA FS, and Robert W. Wescom, USDA NRCS, Institute of Pacific Islands Forestry, 1151 Punchbowl St., Rm. 323, Honolulu, HI 96813.
User Rating: 4 / 5
Research and Technology Transfer Needs for the Next Millennium
EXECUTIVE SUMMARY
Association for Temperate Agroforestry
Columbia, Missouri
Fall 2000
Funding for this project was provided by the USDA National Agroforestry Center
TABLE OF CONTENTS
Agriculture needs agroforestry
Agroforestry is relevant to many issues
Agroforestry provides benefits in many settings
It has happened slowly but surely. Over the last two or three decades dramatic adjustments to farmland management and ownership have changed the face of the American "farmscape." one alarming change is that a significant portion of prime farmland and ranchland is being lost to development (e.g., converted to home sites, factories, roads, and shopping centers). In the U.S. an estimated fifty acres of farmland is now lost every hour of every day to development pressures. Similarly, forest cover in the U.S. has started to decline after remaining essentially constant since the 1920s. As the U.S. population continues to increase by three million each year, forestry and agriculture will both face the problem of meeting an increasing demand for goods, as well as for an expanding array of services, such as clean water, recreation, and wildlife habitat. More importantly, society will have to meet its needs with a fixed or shrinking land base.
Agriculture and forestry share many goals and over the centuries they have provided the strategic foundation for our country. Together they comprise more than 75 percent of the land use in the U.S. Too often there is a tendency to treat agriculture and forestry separately when addressing natural resource concerns. Yet, a high proportion of the watersheds and landscapes in this country are an interwoven mosaic of both uses. Rural communities often depend on both agriculture and forestry to remain economically viable. Solutions are needed that build from a comprehensive, all-lands approach. Otherwise, it is like trying to make a patchwork quilt without bothering to sew the pieces together -- everything comes unraveled.
Technology can provide some productivity gains as improved crops become available through biotechnology and genetic engineering, but the heavy reliance on fertilizers and pesticides already is manifesting its own not-too-subtle impact on the environment. Likewise, consumers and producers are engaged in a lively debate on food safety and environmental issues related to the production and consumption of genetically modified crops. In the future, agriculture may be able to produce sufficient food to meet the world's demand but production costs will rise and so too will the cost of food and the potential for negative impacts to the environment.
Ultimately the challenge will be to find ways to sustain the provision of goods and services that society derives from forests and agriculture in ways "...that meet the needs of the present without compromising the ability of future generations to meet their own needs."
Agriculture Needs Agroforestry
When the USDA National Commission on Small Farms Report was issued in January 1998, it listed several recommendations on agroforestry and concluded that .... "USDA extension, conservation, and forestry services should make greater efforts to promote and support agroforestry as part of an economic and ecological strategy for a healthy agriculture."
Today, many farmers and ranchers are struggling to make a livelihood on small acreage farms. They often have limited financial means and are seeking ways to maximize their income per acre, while keeping their requirement for purchased inputs low. Production systems need to become more diverse. New crops and new production methods need to be embraced. Cost-effective alternatives that can meet environmental goals and increase profits need to be available to producers.
A more diversified agricultural sector means producers will need to select from a broad portfolio of management practices; practices that include science-based agroforestry technologies. Most agroforestry practices are designed to be readily integrated into existing farm operations. In many instances, the adoption of one or several agroforestry practices can be the difference between profitability and economic loss.
The U.S. made a commitment to sustainable forest management when it signed the Santiago Declaration in 1995. However, there are places in the U.S. that are already experiencing difficulty meeting society's expectations for some forestderived benefits. For example, in many areas land use fragmentation patterns across the landscape have resulted in the reduction of many plant and animal species that rely on forest habitat. In other regions there are projections of inadequate wood supply. Insufficient water quality and aquatic habitat are issues that now affect most regions.
If society's needs and aspirations for forestderived goods, services, and amenities truely are to be met, we must find ways of augmenting traditional forestry by gleaning some portion of these benefits from agricultural lands. For example:
• Windbreaks can provide corridors across agricultural lands to connect forest fragments and increase wildlife benefits, while protecting soils, crops, and livestock, conserving energy, and producing commercially valuable products.
• Riparian forest buffers on farms and ranches can protect surface waters from sediments, nutrients, and contaminants, while enhancing aquatic habitats, producing marketable products, and sequestering carbon.
• Fast-growing hybrid poplar trees grown on farmlands can treat agricultural waste and provide income for farmers, while helping to meet the demand for wood fiber and energy.
• Farm woodlots can be used to grow specialty products such as ginseng or mushrooms under a modified forest canopy, thereby encouraging timber stand improvement practices.
• Grazing/timber systems allow farmers to generate an annual income from grazing livestock under thinned forest stands while producing high quality sawlogs.
A comprehensive approach is needed to increase the investment in developing and implementing agroforestry practices in the U.S. This needs to occur through an expansion of existing state and federal agency programs, an increased use of landowner assistance programs and by explicitly including agroforestry in competitive research grant and extension programs.
Agroforestry is Relevant to Many Issues
With more than eighty percent of Americans now living in urban or suburban environments, it has become increasingly important that the public understand that much of what it values is derived from agriculture and forestry. People need to understand that clean water does not just happen; that the food and fiber they consume and the wastes they generate have associated consequences and responsibilities.
There is no shortage of issues that agroforestry can help resolve. Although many resource professionals and landowners don't yet understand the full benefits of adding agroforestry practices to their land management portfolio, many are beginning to investigate the possibilities. Most farmers, ranchers, and communities cannot afford to plant trees or shrubs simply because it's the right thing to do. It's hard to be virtuous when you're in a daily struggle to make ends meet. But once a landowner in an area implements an agroforestry practice that successfully solves a problem, agroforestry often begins to "sell itself' to his or her neighbors.
Agroforestry practices are grouped into five categories: 1) alley cropping, 2) forest farming, 3) silvopasture, 4) riparian buffers, and 5) windbreaks. This document describes agroforestry practices within each of these categories and lists associated high priority research questions and technology transfer needs.
There are some common needs that apply to all agroforestry practices. More regional workshops and field demonstration projects can help illustrate both the logistics and the economics of an agroforestry practice to resource conservation professionals and landowners. The generation of educational materials, such as videos and "how-to" manuals, that provide specific guidance on how to design, install, and manage agroforestry practices, along with innovative extension/outreach programs, will facilitate more local adoption. The networking and integration among resource agencies at the national, state, and local levels needs to increase.
Since agroforestry is a hybridization of agriculture and forestry conservation and production technologies, landowners need to be able to evaluate the economic performance of an agroforestry practice against traditional forestry and agricultural cropping alternatives. In most instances there remains a need to better characterize the economic cost for establishment and maintenance of an agroforestry practice and its economic return. This must include considerations of financial risk and operational complexity. Region-specific economic analyses are needed that present information in ways that natural resource professionals and landowners can understand. In many areas landowners are seeking advice on how to form cooperatives to harvest and market new products.
Agroforestry practices have been shown to provide benefits in many settings:
• Carbon Storage: Sequesters large amounts of carbon in trees and shrubs across a large landbase.
• Pest Management: Provides habitat for beneficial insects and birds. Presents a physical barrier that interrupts pest cycles.
• Soil Conservation: Reduces loss of soil organic matter, nutrients, and soil particles.
• Streams and Lakes: Protects water quality by intercepting sediments and agricultural chemicals. Reduces streambank erosion and improves aquatic habitat.
• Water Conservation: Reduces evaporation and plant transpiration, beneficially distributes snowmelt, and protects riparian zones from agricultural runoff.
• Wildlife Habitat: Provides food, cover, nesting sites, and travel lanes.
• Economic Benefit: Provides income from trees and their products, while allowing for annual income from crop and livestock production. Improves crop yield and quality.
• Livestock: Protects livestock from harsh climate, improves animal health, and lowers feed costs. Provides annual income from grazing/timber systems. Moderates noise and odor from animal operations.
• Aesthetics: Provides plant diversity, wildlife habitat, and recreational corridors.
• Energy Conservation: Reduces energy costs associated with farm operations.
Two incomes in the space of one... Making a living from year to year off an annual crop is fraught with uncertainty. Success depends on weather conditions and favorable markets at harvest. Alley cropping systems provide a way to lower risk by diversifying production. In alley cropping an agricultural crop is grown simultaneously with a long-term tree crop to provide annual income while the tree crop matures. Traditionally, fine quality hardwoods such as walnut, pecan, and oak have been preferred species, as they can be managed to produce high-value lumber or veneer logs. More recently, fast-growing hybrid poplar trees are being grown for sawtimber in 15-20 year rotations. When nut-bearing trees are used, they can provide an intermediate product for sale. In addition to improving annual cash flow, these systems also protect annual crops from wind, reduce soil erosion, and provide wildlife habitat. Most row, grain, and forage crops, as well as specialty crops, such as catnip or St. John's Wort, have been shown to grow well in an alley cropping system.
Research Questions
The level of investment in research on alley cropping must increase. More information is needed to provide the scientific basis for designing practices that can meet an expanding set of landowner and societal objectives. AFTA has identified the following high priority research questions:
Technology Transfer Needs
The level of investment in technology transfer on alley cropping must increase. Increased technology transfer efforts should focus on packaging completed, but scattered, research results to facilitate their use by resource professionals and landowners. AFTA has identified the following high priority information needs:
Made in the shade... Many farmers who own woodlots are finding they can make money in the shade. Many high-value specialty crops are now being cultivated under the protection of a forest canopy that has been modified to provide the appropriate microclimate and light conditions. Meanwhile, the timber stand improvement activities that are carried out to develop the appropriate understory conditions, like thinning less desirable stems and pruning lower branches on the eventual "crop" trees, can result in the production of clean, knot-free wood of higher value as a long-term economic strategy. Shade tolerant crops such as ginseng, goldenseal, shiitake mushrooms, and decorative ferns are being grown and sold for medicinal, culinary, or ornamental uses.
Research Questions
The level of investment in research on forest farming must increase. More information is needed to provide the scientific basis for designing efficient production practices. AFTA has identified the following high priority research questions:
Technology Transfer Needs
The level of investment in technology transfer on forest farming must increase. Increased technology transfer efforts should be focused on packaging completed, but scattered, research results to facilitate their use by resource professionals and landowners. AFTA has identified the following high priority information needs:
Water matters... Many of the waters in the United States are polluted to the extent that they can no longer be safely used to supply drinking water, for swimming and other recreation opportunities, or to provide edible fish. Much of the loss of water quality has been shown to be a result of non-point source pollution from agricultural activities. Practices like cropping and grazing often occur up to the edges of streams, lakes, ponds, and wetlands. The result is a loss of aquatic habitat and high levels of sediment and chemical inputs which lower water quality. Forested riparian buffer practices consisting of grasses, shrubs, and trees have been shown to be an effective strategy for improving water quality by intercepting sediments, filtering excess nutrients, and degrading pesticides. They also can stabilize streambanks, protect floodplains, enhance aquatic and terrestrial habitats, and provide landowners with harvestable products.
Research Questions
The level of investment in research on riparian forest buffers must increase. More information is needed to provide the scientific basis for designing buffers that can meet an expanding set of landowner and societal objectives. AFTA has identified the following high priority research questions:
Technology Transfer Needs
The level of investment in technology transfer on riparian forest buffers must increase. Increased technology transfer efforts should be focused on packaging completed, but scattered, research results to facilitate their use by resource professionals and landowners. AFTA has identified the following high priority information needs:
Trees grow old but so do farmers... Many farmers who own conifer woodlots simply wait for the trees to grow bigger and then take whatever price they can get for a once in a lifetime harvest. Unfortunately, the price often is low due to the lack of timber stand improvement activity throughout the rotation. Thinning less desirable stems and pruning lower branches on the eventual "crop" trees could have resulted in the production of clear, knot-free wood of higher value. Fortunately, agroforestry silvopasture practices are conducive to promoting forest management, while generating forage production in the understory that is suitable for livestock grazing.
Recent research has shown that many cool- and warm-season grasses and legumes yield high levels of quality forage when grown under as much as fifty percent shade. This knowledge is being used to design integrated timber/grazing practices in conifer stands that allow high value sawlogs to be grown as a long-term product, while on the same acre, an annual income can be generated from grazing livestock. Silvopasture field studies have shown that the "crop" trees continue to grow well, while the level of forage production is similar to that of an open pasture.
Although it takes longer, it is also possible to establish tree seedlings in an open pasture or crop field. Trees must be protected from grass competition and animal grazing until they reach adequate size. In the meantime, the trees displace very little land from grazing or crop production during the initial years of establishment. Research has also begun to evaluate the potential for silvopasture with hardwood species.
Research Questions
The level of investment in research on silvopasture practices must increase. More information is needed to provide the scientific basis for designing silvopasture practices that can meet an expanding set of landowner and societal objectives. AFTA has identified the following high priority research questions:
Technology Transfer Needs
The level of investment in technology transfer on silvopasture must increase. Increased technology transfer efforts should be focused on packaging completed, but scattered, research results to facilitate their use by resource professionals and landowners. AFTA has identified the following high priority information needs:
Wind happens .... In the summer, hot dry winds deplete water resources by increasing surface evaporation and elevating plant transpiration rates. Exposed soil can become subject to wind erosion and unprotected crops can be stressed. Odors associated with livestock can be transported long distances, as can spray drift from the application of agricultural chemicals and dust from farming operations. In the winter, the chilling effects of wind and drifting snow often cause hardships to farm families and their livestock, as well as to rural communities.
The concept behind windbreaks is not new. They are also referred to as "shelterbelts" and have been used extensively in the United States since the "dust bowl" era of the 1930s and now comprise about 1.5 million acres. A windbreak's major function is to reduce wind speed. Therefore, a windbreak can be defined as any barrier that reduces troublesome winds by creating a wind shadow to the leeward (downwind) side. An agroforestry windbreak is one that utilizes single or multiple rows of trees and/or shrubs that are integrated into agricultural systems.
What is new is the expanding array of issues windbreaks are being asked to address. While an extensive body of knowledge and technical guidelines has been developed, past efforts have been concentrated on the use of field windbreaks to prevent soil erosion, protect crops from drying winds, and deflect blowing snow. Today, windbreaks are being used for a wide variety of purposes.
Research Questions
The level of investment in research on agroforestry windbreaks must increase. More information is needed to provide the scientific basis for designing windbreaks that can meet an expanding set of landowner and societal objectives. AFTA has identified the following high priority research questions:
Technology Transfer Needs
The level of investment in technology transfer on agroforestry windbreaks must increase. Increased technology transfer efforts should be focused on packaging completed, but scattered, research results to facilitate their use by resource professionals and landowners. AFTA has identified the following high priority information needs:
User Rating: 4 / 5
Edited by Shibu Jose and Andrew Gordon
Springer, Advances in Agroforestry Series, Volume 4
2008, 314 pp., ISBN: 978-1-4020-6571-2, Hardcover
Publisher's List Price $219.00
Jose and Gordon's Toward Agroforestry Design is an important reference for anyone interested in exploring or managing the physiological and ecological processes which underlie resource allocation and plant growth in agroforestry systems.
Drawing together a wide range of examples from around the world, the book highlights how recent developments in agroforestry research can contribute to understanding agroforestry system function, and discusses the potential application of agroforestry in addressing a number of environmental and socioecomic issues.
With examples from a wide range of environments - from tropical moist to temperate and semi-arid - the book makes an important step in bringing together the diversity of existing research and starting to draw out common themes and principles which influence these very different systems.
The case studies are divided into sections which cover above-ground processes, below-ground processes, and methodological advances, each section providing an overview of how these studies can contribute to developing conceptual models or frameworks for exploring more specific agroforestry processes. The book concludes with a synthesis of the key questions and research gaps highlighted throughout the text, together with an overview of the potential for applying this kind of knowledge in developing successful agroforestry systems in the future.
Reviewers recommendations:
TABLE OF CONTENTS
Part I. Understanding Agroforestry Systems: recent advances and future applications
Part II. Resource Allocation in Agroforestry Systems: above-ground processes
Part III. Resource Allocation in Agroforestry Systems: below-ground processes
Part IV. Towards Better Understanding: analytical and modeling tools for agroforestry
Part V. Applying Ecological Knowledge to Agroforestry Design
User Rating: 4 / 5
By Mariah Cornwoman, Twin Tails Farm, Tonasket, WA
Even before we purchased our property, we had a checklist of environmental parameters that we were looking for. We wanted a piece with a number of small environmental niches and species diversity. We wanted both conifer and hardwood species in the forest. We have a perennial, spring-fed creek that runs on the diagonal across our land. We have ponderosa pine and open sage on the dry, southwest-facing slope. We have Douglas fir and tamarack with fescue meadows on the moist, northeast-facing slope. And there are several deciduous species including aspen, douglas maple and water birch along the riparian zone of the creek, with a number of small benches outside the no-cut zone.