The many benefits of agroforestry are well-documented, from ecological functions such as biodiversity conservation and water quality improvement, to cultural functions including aesthetic value. In North American agroforestry, however, little emphasis has been placed on production capacity of the woody plants themselves, taking into account their ability to transform portions of the landscape from annual monoculture systems to diversified perennial systems capable of producing fruits, nuts, and timber products. In this paper, we introduce the concept of multifunctional woody polycultures (MWPs) and consider the design of long-term experimental trials for supporting research on agroforestry emphasizing tree crops. Critical aspects of long-term agroforestry experiments are summarized, and two existing well-documented research sites are presented as case studies. A new long-term agroforestry trial at the University of Illinois, “Agroforestry for Food,” is introduced as an experiment designed to test the performance of increasingly complex woody plant combinations in an alley cropping system with productive tree crops. This trial intends to address important themes of food security, climate change, multifunctionality, and applied solutions. The challenges of establishing, maintaining, and funding long-term agroforestry research trials are discussed

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Since 1985, land retirement has been the primary approach used by the federal government for environmental protection of agricultural landscapes, but increasingly it is being supplemented by conservation initiatives on working lands. This shift logically supports agroforestry and other multifunctional approaches as a means to combine production and conservation. However, such approaches can be complex and difficult to design, contributing to the limited adoption in the USA. To understand and improve the integration of multifunctional landscapes into conservation programs, we worked with 15 landowners in a collaborative design process to build unique conservation plans utilizing agroforestry. We interviewed participants before and after the design process to examine the utility of a personalized design process, applicability of agroforestry to conservation programs and pathways to improve conservation policy. We found that landowners strongly preferred working in person for the design process, and being presented a comparison of alternative designs, rather than a single option, especially for novel systems. Agroforestry was seen as a viable method of generating conservation benefits while providing value to the landowners, each of whom stated they were more inclined to adopt such practices irrespective of financial assistance to do so. For conservation programs, landowners suggested reducing their complexity, inflexibility and impersonal nature to improve the integration of multifunctional practices that appeal directly to the practitioner's needs and preferences. These findings are valuable for conservation policy because they complement previous research theory suggesting the value of working collaboratively with landowners in the design of multifunctional landscapes. Personalized solutions that are developed based on the unique characteristics of the local landscape and the preferences of the individual landowner may be retained beyond a specified payment period, rather than being converted back into annual crop production.

Robusta coffee (Coffea canephora Pierre ex Froehner) is an important cash crop in the lowland tropics. Similar to Arabica (C. arabica L.), agroforestry is common in these systems, though comparatively little is known about how nutrient inputs and leguminous shade trees influence Robusta nutritional status and yield. We evaluated how shading with leguminous trees across four input systems, defined largely by quantity and form (compost vs. synthetic) of nitrogen (N), phosphorus (P), and potassium (K), influenced Robusta-based cropping systems in the Ecuadorian Amazon. Soil fertility was largely unaffected by compost and synthetic fertilizer (NPK) inputs or by shade species, and was weakly related to coffee productivity based on principal component analysis (PCA). Though litter appeared to be an agronomically appreciable source of N and P, this was only somewhat reflected in soil extractable N and P, presumably due to nutrient losses under high rainfall conditions (>3,000 mm yr −1 ). Patterns of variation suggest transfer of N and P from litter to soil to leaf. Conversely, litter K was unrelated to soil K, but soil K was closely related to leaf K. Robusta yields appeared to be largely N limited and were more influenced by input type (i.e., synthetic vs. organic nutrient sources) than by shade species or amount of N inputs in the form of compost or synthetic N, P, and K fertilizers. Additionally, yields across all treatments were significantly higher than regional averages, suggesting that slight investments in inputs can substantially increase productivity in maturing Robusta systems, irrespective of shade tree species selection. INTRODUCTIONCoffee (Coffea spp.) is a globally important cash crop produced in the tropics (Lewin et al., 2004). Worldwide, coffee production is dominated by two species, Arabica (C. arabica L.) (57%) and Robusta (C. canephora Pierre ex Froehner

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