North American Agroforestry. Группа авторов

policy measures that are needed to enhance and preserve the important values of small farms; they recommended specifically that agroforestry offers small farm operators a means for economic diversification, windbreaks, biological diversity, and habitats for wildlife. The original publication was followed by another that offered specific legislation to support agroforestry (USDA, 2003). The report suggests that the USDA, through its 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. Of particular significance in establishing agroforestry policies and programs at the national level was the USDA Agroforestry Strategic Framework (USDA, 2011), which signified a major shift in the USDA’s position on the value of agroforestry in today’s agriculture. The strategic framework created a “road map” for advancing the science, practice, and application of agroforestry, broadening the USDA’s role in agroforestry beyond that of just the National Agroforestry Center. For “buy‐in” purposes, five USDA agencies and two non‐USDA partners (The National Association of Conservation Districts and the National Association of State Foresters) were brought together to develop the framework in collaboration with stakeholders across the United States. In 2019, the USDA updated its Agroforestry Strategic Framework based on current agency needs and priorities, as well as additional input from partners and stakeholders (USDA, 2019). Within the farming and forestry sectors there is a growing trend toward the fragmentation of lands and expanded ownership by a larger group of small landowners, particularly in the eastern part of the country. Agroforestry can enhance the economic viability of owning and managing these units through the production and marketing of comparatively short‐rotation, high‐value specialty items in forest farming practices (e.g., see Chapter 9). Highly visible agroforestry programs that specifically address pressing environmental problems could greatly improve the public’s image of agriculture and forestry as well as the agencies responsible for them. This could have important implications for their political futures.

      Private Organizations

      There is a wide variety of private groups—environmental organizations (e.g., Audubon, A Greener World, The Nature Conservancy, Trees Forever, the Sierra Club), foundations (e.g., Kellogg, McKnight, Pew Charitable Trust, Walton, Winrock), and institutions (e.g., the Land Institute, Rodale Research Center, Wallace Institute, Green Lands Blue Waters)—that are dedicated to finding alternative solutions to environmentally damaging land use practices and to rural development problems. Their diversity of interests often hinders collaboration as well as their meaningful interaction with governmental agencies and private individuals, organizations, and corporations. Because of its integrated approach, agroforestry might provide an opportunity for various audiences to develop a common agenda and approach for conservation and sustainable land use, particularly at a landscape level. Such cooperation could help everyone better understand divergent perspectives, thereby helping alleviate some of the constant pressures that exist between organizations with different concerns and goals. The Savanna Institute, formed in 2013, is a 501(c)(3) nonprofit organization working to lay the groundwork for widespread agroforestry in the U.S. Midwest. The Savanna Institute works in collaboration with farmers and scientists to develop perennial food and fodder crops within multifunctional polyculture systems grounded in ecology and inspired by the savanna biome. Private foundations also initiate new innovative programs that support agroforestry and enhance public agency competitive grant programs (e.g., Agroecology Fund, Cedar Tree Foundation).

      Opportunities for the Scientific Community

      The development of a domestic agroforestry program for the United States offers unique opportunities for the scientific community that embraces forest and agricultural sciences and can provide the opportunity for focusing issue‐based science to address some of today’s most complex problems. The scientific community currently is being challenged to search for viable solutions to complex environmental problems that are beyond its capabilities to address with customary precision and certainty (Burke et al., 2017). Consider the environmental and economic problems facing farmers and foresters today compared with the relatively simple production needs of the last century (National Research Council, 1996; Sampson & Hair, 1990). Agroforestry research experience in developing countries has shown it to be an effective means for interdisciplinary research teams to approach land use issues, in particular diagnosis and design methodologies (Murray & Bannister, 2004; Raintree, 1987, 1990). Similar work in Europe and North America now emphasizes the universality of ecological and socioeconomic issues, thereby blurring the distinction often made between domestic and international problems (Buck, 1995; Lovell et al., 2018). Agroforestry in developing countries is progressing with a combination of support from the research community (e.g., the World Agroforestry Center) and from the development assistance community (e.g., Heifer International) in promoting such practices. This is also beginning to unfold in the United States, in which both the underlying biophysical and socioeconomic science and broader knowledge infrastructure for agroforestry is beginning to reach critical mass, combining “bottom up, high touch” farmer‐to‐farmer approaches and “top down, high tech” scientific breakthroughs.

      There is a growing interest in landscape level research on more sustainable land use systems that provide both income for farmers and ecological services for society (Lovell et al., 2010). Agroforestry concepts and applications provide ample opportunity to do just that (Brown et al., 2018; Palma et al., 2007a, 2007b). Research is now underway that demonstrates how those two objectives can be combined, providing opportunities for the scientific community to explore and identify new integrated land use options (Brown et al., 2018). Agroecology, eco‐agriculture, and regenerative agriculture principles integrate biophysical, social, and economic factors at the landscape level and represent promise for moving agroforestry to the landscape level (Altieri, Nicholls, & Montalba, 2017; Geertsema et al., 2016; LaCanne & Lundgren, 2018; Liebman & Schulte, 2015; Scherr & McNeely, 2007).

      Domestic agroforestry falls along the continuum of agroecology and regenerative agriculture, presenting a need for new types of information—a challenge that breeds creativity and vitality within the research community. Regardless of the scope, domestic agroforestry offers many opportunities for professional development arising from new research projects, education and training programs, and cooperative ventures with public agencies and private organizations.

      Opportunities for the Development of New Knowledge Systems

      In his review of the science of agroforestry, the director general of ICRAF argued that the key challenge posed by this field to the agricultural and forestry research communities is to develop a predictive understanding of the competition, complexity, profitability, and sustainability aspects of agroforestry practices (Sanchez, 1995). This would appear to hold true for the United States as well as developing, tropical countries. To evaluate these four key criteria for the performance of agroforestry, a sound understanding is needed of ecological processes (Ong & Huxley, 1996) as well as socioeconomic and policy conditions that affect agroforestry practices (Buck, 1995; Garrett & Buck, 1997) and how they can be optimized through management.

Innovative agroforestry practices in the United States encompass numerous characteristics and unique associations of component species as landowners experiment with various perennial and annual species, often in unconventional niches. Most of these associations have not been studied, thus significant knowledge gaps exist. A recently completed national assessment provides a science‐based synthesis on the use of agroforestry for mitigation and adaptation services in the face of climatic variability and change. It serves as a framework for including agroforestry systems in agricultural strategies to improve productivity and food security and to build resilience in these landscapes. It also provides technical input on the need for innovative strategies to address significant climatic variability challenges faced by U.S. agriculture (Schoeneberger et al., 2017). Furthermore, the assessment reviews the social, cultural, and economic aspects of agroforestry and the capacity of agroforestry systems to provide multifunctional solutions. In addition, it presents a comprehensive North American perspective on the strengths and limitations of