Agroforestry practice and policy in the United States of America

Agroforestry practice and policy in the United States of America

Fores~~~logy Management Forest Ecology andManagement91 ( 1997)5- 15 Agroforestry practice and policy in the United States of America H.E. Gene Garret...

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Fores~~~logy Management Forest Ecology andManagement91 ( 1997)5- 15

Agroforestry practice and policy in the United States of America H.E. Gene Garrett a,*, Louise Buck b a School of Natural Resources, University of Missouri, Columbia, b Department of Natural Resources, Cornell University, Ithaca,

MO, USA NY. USA

Abstract Agroforestry practices and the policies influencing development and adoption within the United States are reviewed. Agroforestry is defined as ‘intensive land-management systems that optimize the benefits from biological interactions created when trees and/or shrubs are deliberately combined with crops and/or livestock’. The five agroforestry systems identified as having importance in the US are tree-agronomic crop systems (alley cropping and intercropping), riparian vegetative buffer strip systems, tree-animal systems (silvopasturing), forest/speciality crop systems (forest farming) and windbreak systems (shelterbelts). A lack of federal policy relating specifically to agroforestry exists. If agroforeshy is to achieve its full potential in the United States, adequatefinancial, institutional and technical support for its development must he provided. Keywordu:

Agroforestry;

Agroforestry

policy;

Alley

cropping;

Siivopasturing;

1. Introduction As recently as the mid-18OOs, forests occupied a large percentage of the continental US. However, beginning in about 1820 and continuing to the recent past, a conversion of timberland to cropland occurred which transformed much of our forested hectarage to crops and pasture usage. Surveys in states from New York to Missouri indicate that some conversion back to woodlands is now underway without significant assistance from governments in facilitating transition practices and cost. In Missouri alone, approximately 120000 new forested hectares developed between 1972 and 1989 (Hahn, 1991). This widely-observed relationship, in lieu of government-facilitated policies, programs and practices, may be taken as a

* Corresponding 1977.

author.

Tel.: (573)

0378-I 127/97/$17.00 Copyright PIf SO3781127(96)03884-4

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Science

882-

Forest farming;

Windbreak;

Riparian

buffer

strip

measure of the strength of a movement of the people to reforest lands perceived as best serving society’s needs in a forested state. While the movement is slow, it is believed that the trend is driven by several societal concerns. 1. Resource: much of the converted forestland now being cropped is not self-sustaining under current or anticipated cropping systems. 2. Economics: where cropping is resource sustainable on marginally-productive lands, it is often sustainable only in a business sense and often only because the practice is government supported. 3. Environment: great concern exists over the quality of our air, water and soil resources. Water and air quality and control of soil erosion stand to be significantly improved as a result of agroforestry practices replacing traditional cropping and pasture practices on marginally-productive agricultural lands.

B.V. All rights reserved.

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4. Social: stable environments are required for an individual’s psychological well-being as well as community development. Forested areas provide recreation and leisure outlets while supporting tourism, recreational and wood-based industries. A convincing case can be made that current landuse patterns reflect not only a significant underutilization of land-based resources in the United States but also that current uses are not totally supported by the people. A growing constituency would like to see a stronger transition from conventional cropping systems to systems that include trees. Unfortunately, no economically-suited method of transition (pure crops to crops and trees) has been available to the landowner and wholesale coverage of the conversion cost by State and Federal governments has been and continues to be prohibitive. A land-use strategy is required which allows landowners who are interested in incorporating trees into their agricultural systems to do so without financial loss. Agroforestry has the potential to do this. Agroforestry, “an intensive land management program that optimizes the benefits from the biological interactions created when trees and/or shrubs are deliberately combined with crops and/or livestock” is a rapidly emerging field in the temperate zone (Garrett et al., 1994). As a field of study, it possesses many qualities that promote the merging of forestry and agriculture and offers the scientific basis for the development of a new, comprehensive and integrative land-use strategy. In many instances, through the sacrifice of some of several output factors (i.e. wood, forage, specialty crops, livestock, etc.) a greater total economic benefit can be derived from a given unit of land than could be obtained by emphasizing only one or two of the product alternatives. Agroforestry provides the landowner with the opportunity to develop a portfolio of short- and long-term investments allowing for some risk spreading through diversification. The diversity of products can help ease some of the reliance farmers have on income from cash grain crops while reducing surpluses. 2. Agroforestry

systems

Agroforestry within the US emphasizes optimal integration of trees with crops. Historically, land

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managers in the temperate zone have co&&red forestry and agriculture as opposing landuse alternatives. However, with a creative design, clear -management objectives, careful planning and skillful application, the advantages of combining forestry and agriculture can outweigh perceived disadvantages. Within the US, agroforestry practices can be grouped into five systems: (I > alley cropping, (2) silvopasturing, (3) windbreaks (shelterbelts), (4) riparian buffer strips, and (5) forest farming. 2.1. Aliey cropping

Alley cropping (intercropping) is a tree-agronomic crop system with widely spaced tree rows. creating alleyways for growing companion crops. This system has been most widely researched in the midwest and its greatest popularity is found in the midwestem and southern US. In this system, tree rows are spaced to accommodate the biological needs of intercrops. Within-row spacings, however, must be close enough to produce a ‘training effect’ while providing a surplus of trees from which one. can select the final crop trees. Closer within-row spacings provide better protection of the site (e.g. erosion control) early in the rotation period. Within- and between-row spacings will vary with tree species and intercrops planted, management objectives (e.g. an emphasis on wood versus fruit production) and even the availability of farming equipment-alleyway widths may be designed to accommodate headers, disks etc. owned by the farmer. Studies-conducted in Missouri, however, have demonstrated that when black walnut fruit and wood production are both emphasized in a production system, a 12 m X 3 m spacing is a good compromise (Garrett et al., 1991). Twelve meters between rows provides sufficient light to accommodate even many shade intolerant cbnventional row crops for up to 10 years. Three meters between trees within the row provides additional trees from which a final 74 ha-’ can be selected. For landowners interested in growing intolerant, conventional row crops for more than 10 years, spacings of more than 12 m between rows is recommended. An east-west row orientation provides maximum light for intercrop species. While some concern has been expressed about the quality of wood grown under open alley cropping

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management conditions, such concerns appear to be unfounded. Cutter and Garrett (1993) reported that height, diameter and specific gravity were greater for alley cropped walnut trees than for trees grown under woodlot-like conditions. Furthermore, based upon growth during the first 17 years, 50-60 year veneer log rotations are projected for alley cropped trees compared with a customary 80-100 years for conventionally-grown trees. Numerous economic assessments have been conducted on agroforestry alley cropping with typical internal rates of return ranging from 4 to 11% (Kurtz et al., 1984). In general, returns tend to increase with management complexity and site quality. Moreover, tree species which yield especially high-value wood products and fruit or other marketable products have obvious advantages over low-value species which produce only wood products. Assessments made of alley cropping on marginal quality farm land have shown that alley cropping produces land expectation values comparable to those of traditional agricultural systems (Lottes, 1985). Furthermore, the planting of valuable hardwood species with nitrogen-fixing woody and herbaceous types has been demonstrated to be an economically viable alternative to conventional row crops on these sites (Gordon and Dawson, 1982). 2.2. Silvopastoral

management

Silvopasturing is a tree-animal system where forages are grown with trees under intensive management for livestock grazing. While it has been researched most extensively in the southern US, its application is prominent in both the southern and western parts of the US and it has great potential in the midwest. However, its greatest potential is in the pine belt of the southern and western US. A total of 40 million ha of pine and oak-pine forestland exists in the South while 16 million ha of forest exist in the three western states of California, Oregon and Washington that are suitable for silvopasturing (Garrett et al., 1994). Silvopasturing is already the most common agroforestry-related practice in the state of Washington and perhaps in the entire western US region (Lawrence et al., 1992). Tree densities associated with silvopastoral management systems in the US vary greatly with tree

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species and age, site conditions and light requirements of forage species. Tree (crown) density greatly influences forage yields (Gaines et al., 1954; Lewis et al., 1984) with yields typically decreasing as tree density, and thus shade, increases beyond a threshold value. However, with proper tree densities and tree/forage combinations, increases in forage yields (Dawson, 1983; Garrett and Kurtz, 1983) and quality (protein, phosphorus content; Pearson, 1991b) may be possible within some silvopastoral practices. Little information has been published on the economics of silvopastoral management. However, indications are that it is an economically viable land-use choice. Grazing a longleaf-slash pine forest for 40 years yielded an average annual net return of $18.88 ha-’ for grazing and $216.36 ha-’ for timber (Pearson, 1991a). Furthermore, a 5-year study of domestic forages under loblolly pine revealed that two out of five alternatives studied yielded greater internal rates of return than the open-grown forage alternative (Clason, 1994). 2.3. Windbreak systems

Windbreak (shelterbelt) systems are perhaps the oldest form of agroforestry in the US. These systems are of noted importance in the more northern, midwestern plains states (Kansas, Nebraska, the Dakotas, etc.) and western states where they are used for stabilizing microenvironments. Beneficial effects leading to increased crop and livestock production are afforded by properly designed windbreak systems. Increases are attributed to reduced wind erosion, improved microclimates, snow retention and reduced crop damage by high winds. In general, wind velocity is altered and benefits are derived to a distance of lo-20 times the height of trees within a windbreak (Brandle et al., 1988). Thus, a 9-m-high windbreak would yield benefits to a distance of 91-183 m on the leeward side. The design and success of shelterbelts has improved dramatically from the early 1930s when single shelterbelts of up to ten rows were recommended on only one side of an area to be protected. Today’s designs advocate either single or combination rows scattered across an area with spacings within the row (e.g. 2.4-3 m) and between rows (e.g. 5.5-6 m> that provide adequate air movement to minimize turbu-

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lence and snow piling. With a properly designed system, protection is assumed to begin in about year 6 and increase over the next 15 years, reaching full protection by age 20. Average yield increases of up to 15% in winter wheat have been observed (Brandle et al., 1984). However, few financial evaluations of costs and benefits from shelterbelt systems have been reported in the US, Three systems in Nebraska with windbreaks spaced at 194, 128 and 66 m were compared. Over an estimated 50-year life span, all three designs were found to yield positive net benefits, which ranged as high as 17% (Brandle et al., 1992). 2.4. Riparian buffer strip systems

Riparian corridor vegetative buffer strips consist of a combination of vegetative types (i.e. trees, shrubs and grasses) which are optimally combined on stream and riverbanks to assist in controlling nonpoint sources of waterway pollution while regulating and protecting aquatic habitats. Such systems have broad application throughout the US but nowhere are they more important than in states that are heavily agricultural. Riparian buffer strip management, perhaps more than any of the other agroforestry systems found in the US, is in need of immediate broadscale adoption for its environmental benefits. Properly designed systems reduce the adverse effects of traditional farming on stream quality, create suitable habitat for a variety of wildlife species including aquatic inhabitants and provide a sustained income from forest products. In the corn belt alone (Illinois, Indiana, Iowa, Missouri and Ohio), more than 137 000 km of streams and riverbanks are unprotected by trees or shrubs. An additional 129000 km are unprotected or have only minimal protection in the heavily farmed states of Kansas, Nebraska, North Dakota and South Dakota (Garrett et al., 1994). Designs consisting of trees along the drainage bordered to the outside by shrubs and finally grasses are becoming more common and have proven to be very effective in filtering out ‘would be’ stream contaminants. Schultz et al. (1993) demonstrated that, of the species studied, combinations of switchgrass (Panicurn virgatum), ninebark (Physocarpus opulifolius), silver maple ( Acer saccharinurn), poplar hybrids (Populus spp.) and willow (Salti spp.> pro-

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duced the greatest amount of above- and belowground biomass in the shortest time and were superior to straight grass buffers. As a result of such combinations of species, infiltration rates increased by as much as eight times compared with adjacent cultivated land. Forested buffer strips 27-46 m in width have also proven to be effective in reducing nitrogen in groundwater by 68-100% and in surface runoff by 78-98% (Lowrance, 1992). While complete assessments of the economic- benefits are lacking, estimates of the cost of cropland sediment in reservoirs run as high as $200 million annually (Crowder, 1987). In Ohio alone, studies have shown that a 25% reduction in soil erosion would result in a saving of $2.7 million in water treatment costs each year (Forster et al., 1987). 2.5. Forest farming

Forest farming consists of creating suitable microenvironments in natural forest stands for growing shade-tolerant specialty crops sold for ornamental. culinary or medicinal uses. Forest farming is currently of greatest importance in the Pacific northwest, northeast and Appalachian states. Its popularity, however, is rapidly growing as woodland owners become more aware of the economic and marketing aspects of special forest products. Naturally forested areas throughout the US provide excellent opportunities for the production of specialty crops. Currently, however, most forest specialty crop production is passive and does not qualify as agroforestry using the strict definition. The potential; however, for increasing the economic gain through intensive management is rapidly being recognized as marketsdevelop for numerous plants common to the understories of our forests. Of the 16 million ha of forest in California, Oregon and Washington. approximately 0.80 million ha are rated as having good potential for conversion to cropland and could yield great financial benefits if placed under forest farming management (Garrett et al., 1994). Recent surveys conducted in the Pacific northwest on the economic and marketing implications of special forest products have been most revealing (Schlosser et al., 1991). In 1989, native plants growing in the understory of forests in the Pacific northwest and coastal British Columbia and sold as floral

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greens created an industry which employed over 10000 workers and generated an estimated $128.5 million in sales (Schlosser et al., 1992). Similarly, the commercial harvest of wild edible mushrooms in the Pacific northwest has grown into a multimillion dollar industry (Molina et al., 1993). In view of such profits without management, one must wonder about the potential of specialty forest products if management (agroforestry) was administered (Schlosser et al., 1991). Other examples of specialty forest products in the US include the pine straw industry of the south, sugar maple in the northeast and ginseng in the midwest and Appalachian areas. Agroforestry land-use involves comparatively complex systems of resource management that seek to satisfy multiple objectives. The knowledge and information required to support the design and development of agroforestry systems, therefore, must be drawn from multiple disciplines and perspectives and integrated to address variable local needs and conditions. Similarly, agroforestry policy must be centrally concerned with supporting systems of knowledge management that enhance and promote synergy among multiple institutional participants including landowners.

3. Policy dimensions

of agroforestry

land use

The United States presently lacks a consistent national policy on agroforestry. Agroforestry development is affected therefore by an array of agriculture, forestry, environment and rural development policies and programs at respective levels of govemment. The sum effect is a limited allocation of resources and set of incentives for land and resource owners, public institutions or non-profit membership groups to participate in agroforestry activities. 3. I. Key factors opment

affecting agroforestry

policy devel-

Perhaps the single most influential factor in the development of agroforestry land-use policy is a constellation of persistent though presently changing social values and presumptions that foster strict segregation of land among uses, and rigid distinctions

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between public and private resource ownership (Kidd and Pimentel, 1992). This strategy reduces the complexity of management and is consistent with our capitalistic drive to focus on the economic ‘bottom line’ in decision-making about the production of food, forage, livestock and fiber (Lassoie and Buck, 1991). Unfortunately, it neglects critical social and environmental issues or ‘externalities’, and is thus inadequate to address the realities of land use decision-making where significant bio-physical and socio-economic limitations are encountered in our efforts to continue maximizing production and profit (Daly and Cobb, 1989; Tisdell, 1990). Natural resource management institutions in the US were forged from these values over many years and will not be readily disassembled. The segregation-of-use concept is embodied also in our urban and regional planning institutions whose widely used tool for this purpose is zoning. Our institutions, however, are evolving as the American public demands more ecologically and socially sound approaches to the management of the nation’s farm and forest lands (Sampton and Hair, 1990). Academia provides growing evidence of this shift in values. The traditional field of agriculture is making room for sustainable agriculture (Hudson and Harsch, 1991) while the field of forestry accommodates new forestry (Gillis, 1990). Simultaneously, new fields such as landscape ecology, restoration ecology, conservation biology and human dimensions of wildlife management signal the need for a scientific basis for managing complex systems in the face of rapidly changing public attitudes toward the conservation of biological resources (Decker et al., 1991). A sequence of four biennial conferences on agroforestry in North America represents an important set of milestones in the development of agroforestry as an interdisciplinary science (Garrett, 1991; Williams, 1991; Schultz and Colletti, 1994; Ehrenreich, 1996). Regional agroforestry symposia and conferences have also been held during this period to review the state-of-the-art of agroforestry policy and practice for specific eco-regions (Henderson, 1991; Kettler, 1995). This literature suggests that agroforestry serves as a useful conceptual model for a broad range of integrative land use management systems at farm and landscape levels.

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policy devel-

To make agroforestry an effective land use alternative requires the design of comparatively complex, management intensive systems for highly variable sets of conditions. To design such systems in turn requires adequate financial, institutional and technical support for the development of appropriate knowledge and information. In certain contexts it may also require financial incentives to landowners to participate during the early stages of system establishment before the benefits of production are fully realized. The past decade of experience with agroforestry in developing countries has taught that much of the knowledge required to develop productive and sustainable agroforestry systems lies with the land user, the farmer (Chambers, 1989). Enabling and valuing the farmers’ capacity to innovate is critical to the agroforestry design process (Raintree, 1987). Likewise, opportunities to draw upon knowledge and information from multiple sectors and disciplines has important advantages over the conventional approach to technology development (Buck, 1993). Among the most important criteria for agroforestry development which policy measures must address is the need for configurations of institutional participants that foster innovation from multiple sources of knowledge and information (Biggs, 1991). This approach contrasts with the ‘conventional linear model’ of agricultural technology development (Roling, 1992). In this conception, improved technology is assumed to be generated by scientific experts, then ‘transferred’ or ‘extended’ to ‘progressive’ farmers through a predictable diffusion and adoption process (Rogers, 1986). The innovator (scientist) waits then for farmers to either accept or reject the offer. If rejected, the science-led innovation process begins again (Roling, 1990). Agroforestry is almost certain not to thrive under the assumptions that govern this type of institutional interaction. Thus, the agroforestry policy designers’ challenge is to overcome the significant institutional obstacles posed by dominant, conventional methods of knowledge management within agricultural, forestry and related domains. A national level assessment of agroforestry land-

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use (Garrett et al., 1994) found that certain programs and traditions within respective resource mdnagement agencies and universities are particularly influential in the formation of landowners’ decisions about practicing agroforestry. Thus, experience from ..these programs will be central to the design and development of effective agroforestry policy. The following discussion draws significantly from this assessment. 3.3. Federal support programs 3.3.1. Conservation

Reserve Program

The Conservation Reserve Program (CRP) pays farmland owners to take highly erodible land out of production for a period of 10 years. The program allows cost-sharing for alley cropping of agricultural commodities when land is planted to hardwood trees. In exchange for permission to produce agricultural commodities, operators are entitled to rental payments of up to 50% of the value of a land Withdrawal contract. The CRP also provides for windbreaks and shelterbelts without requiring enrollment of the entire field. The CRF’ has been criticized for its high cost and inequitable distribution of benefits, but is recognized for generating important conservation, wildlife and environmental benefits (Soil and Water Conservation Society, 1994). An option for addressing the pervasive question of “what happens when contracts expire” (Heimlich and Osbom, 1994) may be to offer program support for the establishment phase of various agroforestry practices. Revenues from well-designed systems would reduce the need for public payments to farmers to conserve natural resources. 3.3.2. National Agroforestry

Center

A Center for Semi-Arid Agroforestry was established in 1990 to integrate activities of various branches of the USDA Forest Service that are strategic to agroforestry development. In 1994, the Center broadened its scope to the national leve1, and in 1995 joined with the USDA, Natural Resources Conservation Service (NRCS) to expand national agency support for agroforestry. The Center works through cooperation and partnerships with other federal and state agencies, universities and conservation organizations to conduct research, develop technologies, establish demonstrations and transfer technol-6gies

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and information to natural resource professionals. Though funding for the Center has been limited, its programs are planned to heighten the visibility of agroforestry as an economically viable, conservation land-use strategy. The Center plays a central role in keeping public policy makers informed on temperate-zone agroforestry (National Agroforestry Center, 1995).

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sures that the ASCS has encouraged under the ACP, however, trees have played a minor role.

3.3.4. Stewardship Incentive Program (SIP) The Cooperative Stewardship Incentive Program stimulates improved management of nonindustrial private forest lands through cost-sharing of approved practices. Landowners must develop an approved forest stewardship plan to qualify for SIP assistance. 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 for a range of productive purposes. In several states, New York for example, SIP is seen to be highly effective in fostering collaboration among land management agencies including universities, and in engaging landowners as innovative partners in the process.

3.3.6. Environmental Easement Program (EEP) The EEP provides for public acquisition of permanent or long-term easements from owners of eligible farms or ranches to ensure the continued conservation and improvement of soil and water resources. Landowners are prohibited from harvesting or selling Christmas trees or nuts on leased lands, though are 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. The EEP provisions fail to take advantage of the potential for agroforestry to help accomplish the program’s conservation objectives, and limit the owner’s range of options for implementing the requisite natural resources conservation management plan. By excluding these practices, opportunities are lost for the landowner to generate income that could help reduce federal expenditures on conservation. A reexamination of the justification and the practical basis for the exclusion of agroforestry-type practices appears warranted. The EEP provides also for a Tree Planting Initiative to encourage reforestation of marginal agricultural lands. The Initiative aims to foster collaboration among agencies and programs concerned with the protective and productive roles of trees in agricultural areas. Thus, it could have a positive role in fostering agroforestry if agency professionals were made aware of its potential in addressing the Initiative’s objectives.

3.3.5. Agricultural Conservation Program (ACP) The longstanding ACP provides cost share assistance to agricultural producers for tree planting to meet conservation objectives. The USDA, ASCS (recently renamed the Farm Service Agency) subsidizes the cost of trees and makes them available to farmers through nurseries. The program is consistent with the goals of agroforestry and marks a comparatively long tradition of the ASCS and NRCS involvement in promoting tree-based conservation practices. Compared with other conservation mea-

3.3.7. Sustainable Agricultural Research and Education (SARE) The Sustainable Agricultural Research and Education @ARE) program’s broad definition of sustainable agriculture speaks directly to potential roles for agroforestry. To date, however, the program has funded few research projects that include tree components. The conventional one to three year time frame for the completion of studies constrains the investigation of many key agroforestry topics and questions.

3.3.3. South-central Family Farm Research Center The USDA’s Agricultural Research Service CARS) initiated a site-based agroforestry systems research program in 1992. The aim is to devise and assess agroforestry systems in the southern Appalachian region of the eastern US that are compatible with combined livestock, tree, pasture and wildlife production, and to evaluate biological, ecological, environmental, and socio-economic interrelationships among the multiple resources.

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3.4. Government price supports and taxes

United States agricultural policy rests on a complex system of price supports and taxes that aim to influence production levels and consumer prices for various 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 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 hectarage reduction programs have placed additional emphasis on conserving soil and water resources for lands thus withdrawn from production. There has not been a surplus production of highvalue timber in the United States, however, and all indications are that the value of wood and wood products will continue to grow. A policy focus on growing high quality timber under field or pasture conditions in agroforestry systems would provide an opportunity for government to overcome problems of surplus without subsidizing growers to produce less. A complementary component to this strategy could be to encourage the development of domestic and foreign markets for tree crops produced in agroforestry systems. 3.5. Agrofarestry research, at land grant universities

extension and education

Agroforestry programs are developing at a number of land grant institutions and interest in agroforestry at universities and colleges throughout the nation is increasing. Such programs have tended to emerge from departments of forestry or natural resources. Successful programs, however, are highly interdisciplinary and depend upon landowner participation throughout the research and technology development process. Among the most long-standing 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 determi-

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nation of a few key individuals who have directed scarce research and education resources to agroforestry despite the absence in most cases of funding dedicated specifically to such activity. Further growth of these programs is limited directly by lack of recognition by policy decision-makers and associated lack of funds. 3.6. State agroforestry

and related programs

Missouri, South Dakota and Iowa have adopted agroforestry legislation that is designed to complement the federal CRP. Based on the demonstrated effectiveness of alley cropping in controlling soil loss from highly erodible lands, state policy makers have sought to encourage more landowners to enroll greater hectarage in this system than would have come about through federal incentives alone. 3.7. Non-projit

membership groups

3.7. I. Association (AFTA)

For

Temperate

Agroforestry

Academic, agency professionals and landowners joined together in 1991 to form AFTA. This growing society provides an umbrella for temperate agroforestry activities via networking and information sharing services to its members. AITA is now the primary sponsor of the biennial conferences on temperate zone agroforestry that have been held since 1989. In recognition of the multi-disciplinary. and interagency perspectives that effective agroforestry development requires, from the beginning these meetings have included landowners and agency-professionals as well as academic representatives. 3.7.2. Landowner

groups

There is a vast though often unarticulated network of membership landowner groups who are sympathetic to agroforestry and sometimes actively. involved 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, as well as various community-based conservation and environmental organizations have members who consciously practice agroforestry, or manage land and resources by means that are consistent with agroforestry princi-

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ples (Buck and Matthews, 1993). Given the comparatively innovative character of their members, the important educational role that they play, and the spirit of volunteerism that infects such groups, public policy that would direct and support their activities in agroforestry would likely have early and far-reaching payoffs. 3.8. Future needs of agroforestry

While factors that are important to the development of agroforestry land use in the United States are beginning to converge, the benefits of agroforestry land use will not be fully realized without the development of an extensive agroforestry infrastructure. Present programs and initiatives are insufficiently conceived or endowed to overcome dominant institutional tendencies to specialize within their respective knowledge and land use domains. 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. Real incentives must be created for traditionally disparate entities to work interactively. Achieving the goal of full implementation will require: 1. decentralized, flexible yet adequately coordinated and empowered institutional mechanisms for planning and managing agroforestry development activities; 2. funds earmarked specifically for agroforestry land use to address the participatory, interdisciplinary and often long-term nature of agroforestry research and the multi-dimensional, inter-sectoral nature of effective technology development; 3. 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 alternative strategies. References Biggs, SD., 1991. A multiple source of innovation model of agricultural research and technology promotion. Pap. No. 6,

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