Abundance and diversity of soil invertebrates in annual crops, agroforestry and forest ecosystems in the Nilgiri biosphere reserve of Western Ghats, India

Biologically mediated soil processes rely on soil biota to provide vital ecosystem services in natural and managed ecosystems. However, land use changes continue to impact on assemblages of soil biota and the ecosystem services they provide. The objective of the present study was to assess the effect of land use intensification on the distribution and abundance of soil invertebrate communities in the Nilgiri, a human-dominated biosphere reserve of international importance. Soil invertebrates were sampled in 15 land use practices ranging from simple and intensively managed annual crop fields and monoculture tree plantations through less intensively managed agroforestry and pristine forest ecosystems. The lowest taxonomic richness was found in annual crops and coconut monoculture plantations, while the highest was in moist-deciduous and semi-evergreen forests. With 21 ant species, agroforestry systems had the highest diversity of ants followed by forest ecosystems (12 species). Earthworms and millipedes were significantly more abundant in agroforestry systems, plantations and forest ecosystems than in annual crop fields. Ants, termites, beetles, centipedes, crickets and spiders were more abundant in forest ecosystems than in other ecosystems. It is concluded that annual cropping systems have lower diversity and abundance of soil invertebrates than agroforestry and natural forest ecosystems. These results and the literature from other regions highlight the potential role that agroforestry practices can play in biodiversity conservation in an era of ever-increasing land use intensification and habitat loss.     

Insect pest problems in tropical agroforestry systems: Contributory factors and strategies for management

Agroforestry trees are attacked by a wide spectrum of insects at all stages of their growth just like other annual and perennial crops. Pest management in agroforestry has not received much attention so far, but recent emphasis on producing high value tree products in agroforestry and using improved germplasm in traditional systems, and emergence of serious pest problems in some promising agroforestry systems have increased awareness on risks posed by pests. Insects may attack one or more species within a system and across systems in the landscape, so pest management strategies should depend on the nature of the insect and magnitude of its damage. Although greater plant diversity in agroforestry is expected to increase beneficial arthropods, diversity by itself may not reduce pests. Introduction of tree germplasm from a narrow genetic base and intensive use of trees may lead to pest outbreaks. In simultaneous agroforestry systems, a number of factors governing tree—crop—environment interactions, such as diversity of plant species, host range of the pests, microclimate, spatial arrangement and tree management modify pest infestations by affecting populations of both herbivores and natural enemies. Trees also affect pest infestations by acting as barriers to movement of insects, masking the odours emitted by other components of the system and sheltering herbivores and natural enemies. In sequential agroforestry systems, it is mostly the soil-borne and diapausing insects that cause and perpetuate damage to the common hosts in tree—crop rotations over seasons or years. An integrated approach combining host-plant resistance to pests, exploiting alternative tree species, measures that prevent pest build up but favour natural enemies and biological control is suggested for managing pests in agroforestry. Species substitution to avoid pests is feasible only if trees are grown for ecological services such as soil conservation and low value products such as fuelwood, but not for trees yielding specific and high value products. For exploiting biological control as a potent, low cost and environmentally safe tool for pest management in agroforestry, research should focus on understanding the influence of ecological and management factors on the dynamics of insect pest-natural enemy populations. Scientists and policy makers in national and international institutions, and donors are urged to pay more attention to pest problems in agroforestry to harness the potential benefits of agroforestry.This revised version was published online in November 2005 with corrections to the Cover Date.     

Ecosystem services in human-dominated landscapes: insectivory in agroforestry systems

Despite of being structurally simpler and species-impoverished than natural forests, agroforestry plantations can act as a secondary habitat for native species and sustain some biodiversity. In particular, insectivores can provide important ecosystem services such as insectivory, indirectly benefiting plants through the reduction of herbivory and increasing productivity, by diminishing herbivores abundance. The lending of these services could occur in agroforestry systems, and in the same magnitude that in natural environments, however it has not yet been assessed whether the direct effect of insectivores over insects and indirect effect on plants differ between natural and agroforestry environments depending on possible modulating factors such as climatic region, type of insectivore, trophic group of the preyed arthropod and length of insectivores experimental exclusion. In this study, through a meta-analysis, it was assessed the provision of ecosystem services by insectivores in agroforestry systems compared to natural systems, contrasting it with the modulating factors mentioned. In general, insectivorous species reduced arthropod abundance and plant herbivory, and increased plant productivity. The magnitude and direction of these effects did not differ between natural and agroforestry systems, and neither did between different climatic regions, type of insectivore, preyed arthropod trophic groups nor experiment length. The effect of insectivores on productivity can vary based on the variable used to measure productivity. Our results evidence the provision of services by the insectivores present in plantations, independently of factors that could modulate its magnitude and direction. In this way, enhancing the existence of these important interactions within plantations could represent a win–win scenario.     

Agroforestry systems of high nature and cultural value in Europe: provision of commercial goods and other ecosystem services

Land use systems that integrate woody vegetation with livestock and/or crops and are recognised for their biodiversity and cultural importance can be termed high nature and cultural value (HNCV) agroforestry. In this review, based on the literature and stakeholder knowledge, we describe the structure, components and management practices of ten contrasting HNCV agroforestry systems distributed across five European bioclimatic regions. We also compile and categorize the ecosystem services provided by these agroforestry systems, following the Common International Classification of Ecosystem Services. HNCV agroforestry in Europe generally enhances biodiversity and regulating ecosystem services relative to conventional agriculture and forestry. These systems can reduce fire risk, compared to conventional forestry, and can increase carbon sequestration, moderate the microclimate, and reduce soil erosion and nutrient leaching compared to conventional agriculture. However, some of the evidence is location specific and a better geographical coverage is needed to generalize patterns at broader scales. Although some traditional practices and products have been abandoned, many of the studied systems continue to provide multiple woody and non-woody plant products and high-quality food from livestock and game. Some of the cultural value of these systems can also be captured through tourism and local events. However there remains a continual challenge for farmers, landowners and society to fully translate the positive social and environmental impacts of HNCV agroforestry into market prices for the products and services.     

Evolution of agroforestry based farming systems: a study of Dhanusha District, Nepal

This paper examines how agroforestry-based farming systems evolved in the Dhanusha district of Nepal following the conversion of forest into agriculture during the early 1950s. Some data are from two focus group discussions with agroforestry farmers and one meeting with agroforestry experts. The farmers?? discussion traced the development of farming practices from 1950 to 2010 to identify the drivers of land use change. The experts?? discussion resulted in a scale to differentiate the prevailing farming systems in the study area considering five key components of agroforestry: agricultural crops, livestock, forest tree crops, fruit tree crops and vegetable crops. Data related to the system components were collected from the randomly selected households. The study reveals that land use had generally changed from very simple agriculture to agroforestry, triggered by infrastructure development, technological innovations, institutional support (subsidies and buy-back guarantees) and extension programs. A range of farming systems with varying degrees of integration was evident in the study area: simple agriculture; less integrated agroforestry; semi-integrated agroforestry and highly integrated agroforestry. The three types of agroforestry systems, which are the focus of this study, varied significantly in terms of farm size, cropping intensity, use of farm inputs, tree species diversity, tree density, home to forest distance and agricultural labour force.     

Mixed forests to mitigate risk of insect outbreaks

The majority of agricultural and forest production systems are typically simplified systems and therefore thought to be sensitive to disturbance. Ecosystems might be less sensitive to disturbance if complexity increases. The resource concentration hypothesis predicts that complexity makes it more difficult for herbivores to find and exploit their food. The natural enemy hypothesis predicts less damage in diverse environments because enemy abundance and diversity remain higher and more stable in environments providing more alternative food sources. We explore the effect of tree diversity in two types of pine stands differing in tree diversity. We ask whether European pine sawfly (Neodiprion sertifer) larval group distribution and larval mortality, imposed by specialist natural enemies, is affected by tree diversity. We find fewer larval groups on pine trees surrounded by non-host trees, indicating that fewer egg-batches were laid. Mortality rates by specialist enemies are not affected by tree diversity but parasitism rates are likely to be higher in larger trees. Herbivores are inhibited by increased tree diversity and density, whereas natural enemies seem to be unaffected, partly increasing the resistance of more diverse forest stands against insect damage. Thus, managing for more mixed forests could mitigate risk of herbivore damage.     

Canopy vs. understory: Does tree diversity affect bee and wasp communities and their natural enemies across forest strata?

Bees and wasps provide important ecosystem services such as pollination and biocontrol in crop-dominated landscapes, but surprisingly little information is available on hymenopteran communities in temperate forest ecosystems. Species richness and abundance of bees and wasps can be hypothesised to increase with plant diversity, structural complexity, and availability of food and nesting resources. By experimentally exposing standardised nesting sites, we examined abundance and species richness of cavity-nesting bees (pollinators), wasps (predators) and their associated parasitoids across a tree diversity gradient in a temperate deciduous forest habitat. In addition, spatial distribution of individuals and species across forest strata (canopy vs. understory) was tested. Abundance and species richness was high for predatory wasps, but generally low for pollinators. Species-rich forest stands supported increased abundance, but not species richness, of pollinators and predatory wasps, and also increased abundance and species richness of natural enemies. In addition, the forests showed a distinct spatial stratification in that abundance of bees, wasps and parasitoids as well as parasitism rates were higher in the canopy than understory. We conclude that particularly the canopy in temperate forest stands can serve as an important habitat for predatory wasp species and natural enemies, but not bee pollinators. Enhanced tree diversity was related to increased hymenopteran abundance, which is likely to be linked to an increase in nesting and food resources in mixed forest stands.     

Population dynamics of herbivorous insects and potential arthropod natural enemies on Alnus species in Kabale district, Uganda

Monitoring populations of pests and their natural enemies under different management situations and seasonal weather parameters provides extremely useful information for taking preventive measures against pest outbreaks. The abundance, spatial and temporal distributions of herbivorous insects and arthropod natural enemies on Alnus species were monitored at four sites in Kabale district, Uganda between June 1999 and August 2000. Chewing insects, dominated by Coleoptera (75%), constituted the majority of insect herbivores sampled. Dominant and potentially serious pests of Alnus included Apion globulipenne, an unidentified Chrysomelidae (Coleopt. 27), Phymateus viridipes, Coloborrtics corticina and a Cacopsylla species (Homoptera: Psyllidae). Spiders were the predominant natural enemies accounting for 64% of the total natural enemies encountered, followed by parasitic Hymenoptera (30%). There were marked spatial and temporal variations in arthropod abundance. Among sites, mean abundance of total insect herbivores and total natural enemies on A. acuminata over 15 months ranged from 3.8–8.5 and 3.3–4.7 individuals per 1-m branch length respectively. Over the same period, mean number of total insect herbivores and total natural enemies on A. nepalensis that was studied at only one site were 11.9 herbivores and 4.2 natural enemies per 1-m branch length. Populations of most insect orders increased in the wet season although the greatest herbivore abundance was evident in the dry season. Further studies are necessary on the impact and management strategies of the potentially important insect pests and natural enemies on Alnus.This revised version was published online in November 2005 with corrections to the Cover Date.     

The role of complex agroforestry systems in the conservation of forest tree diversity and structure in southeastern Ghana

The role of different agroforestry systems in the conservation of plant diversity and forest structure has not been directly compared in many agricultural dominated landscapes. In this study, we investigated tree diversity and forest structure in a complex agroforestry landscape traditionally grown for cocoa and mixed food crops and compared these to the natural forest in southeastern Ghana. The study was carried out using 36 25 m × 25 m plots. There was significant difference [95% Confidence Interval (95% CI)] in the native forest/non-crop tree species richness between the natural forest and the agroforest farmlands but species richness was similar between the cocoa and mixed food crops agroforests. The density of native forest/non-crop trees was significantly higher (P < 0.05) in the natural forest but similar between cocoa and mixed food crops agroforest. Similarly, the basal area of native forest/non-crop trees was significantly higher (P < 0.05) in the natural forest but comparable between cocoa and food crops agroforest. Of the 20 most abundant native forest/non-crop trees recorded, 12 of them showed significant responses (P < 0.05) to land use change with nine of the species significantly abundant in the natural forest relative to the agroforest systems. Eighteen native forest/non-crop trees species in the agroforestry systems were commonly recorded as being used; 100% of them being used as fuel wood with 83.3 and 77.8%, respectively, used as medicines and materials. The findings of this study suggests that although complex agroforestry systems are a poor substitute for the natural forest the heterogeneous mosaic landscape in which complex agroforestry forms part can be strategically managed to maximize the benefits of both sustainable agriculture production and conservation of plant diversity by acting as buffer between protected areas and intensively managed areas.     

Plant diversity and arthropod communities: Implications for temperate agroforestry

Polyculture in crop agroecosystems has been examined in numerous studies with the aim of reducing pest populations by increasing diversity among insect populations over those found in traditional monoculture. Resource concentration and enemies hypotheses predict decreased pest populations in more diverse plant communities. Although results have been mixed, insect diversity has been generally increased in polyculture over traditional monoculture. Maintaining natural insect diversity in managed forests to limit possible pest outbreaks has been the goal in forestry systems. Increased arthropod diversity with increased tree diversity has been observed, though fewer studies have been conducted in forestry compared to agriculture. Agroforestry holds promise for increasing insect diversity and reducing pest problems because the combination of trees and crops provides greater niche diversity and complexity in both time and space than does polyculture of annual crops. This revised version was published online in August 2006 with corrections to the Cover Date.     

Design and development of agroforestry systems for Illinois,USA: silvicultural and economic considerations

Recommended managerial inputs and associated outputs expected from practicing agroforestry on marginal farm lands in the central USA are discussed. Modeled management combinations are based on five timber species, three sites indices, three timber growth rates, five agricultural crops, all common crop rotations, and three tillage systems. Black walnut (Juglans nigra L.), combined with row crop production, is used to illustrate a specific multicropping alternative. Based on net present value, modeled agroforestry systems incorporating black walnut performed better on the better sites and at the medium to high timber growth rates whereas management systems using red oak (Quercus rubra L.) with row crops performed better on the poorer sites and at the lower growth rates. For agroforestry to be competitive with traditional agriculture, medium to high timber growth rates were necessary. Also, lower interest rates and the existing U.S. income tax structure favored agroforestry versus traditional agriculture. Substantial increases in net income may be possible through incorporating other income producing activities such as nut production within the agroforestry system.     

Pests and diseases in agroforestry systems of the humid tropics

Few studies have included detailed investigations of the interactions of agroforestry techniques with pests and diseases, although the relevance of such interactions has long been recognized. The objectives of this review are to provide basic information on pests and diseases in tropical agroforestry systems and to develop concepts which can assist in the future in the systematic data collection and analysis in this field. The emphasis is on simultaneous agroforestry systems with annual and perennial crops, although rotational systems are also discussed. Crop rotation is an important pest and disease control strategy in annual cropping systems, and the principle of altering host with non-host plants can also be applied in improved fallow systems, provided that hosts of crop pests and diseases are avoided when selecting the fallow species. When annual cropping systems are transformed into simultaneous agroforestry, the control strategy of frequent disturbance of pest and disease populations is to some extent substituted for the strategy of increased stability and internal control mechanisms. However, reduced pest and disease risk is not automatically achieved by introducing perennial plants and increasing the plant diversity in a system. If plant species are introduced that harbor pests or diseases of other species in the system, the risk of pest and disease outbreaks may actually increase. For evaluating such risks, it is important to consider host-ranges of diseases on the pathovar instead of the species level. Beside the selection of compatible plant species, their spatial arrangement may be important for reducing the spread of pest and disease organisms through the system, although little information is available on such effects, and they may be largely irrelevant for organisms with efficient dispersal mechanisms such as wind-dispersed fungi. In addition to the species-specific, biological effects of plants on pests and diseases, their unspecific, physical effects can be of major relevance for pest and disease development as well as the susceptibility of the affected plant species. Increased pest and disease incidence has often been observed directly at the tree-crop interface, caused by the humid microclimate, physical protection of mammal and bird pests by the trees and eventually reduced pest and disease tolerance of competition-stressed crops. Linear tree plantings and hedgerows affect the wind transport of small insects and disease propagules, the active immigration and emigration of pest organisms as well as the populations of natural enemies. Similarly, overhead shade has a major effect on the micro-climatic conditions under which pest and disease organisms, their natural enemies and the crops themselves develop, and its optimization is a highly efficient control strategy for many pests and diseases. On infertile soils, the susceptibility of crops to pests and diseases is strongly affected by the availability of plant nutrients, which may be influenced by agroforestry techniques in various ways. Soil management measures such as mulching and planting cover crops may affect crop health by improving soil fertility and by directly acting on pest and disease populations. The importance of a more systematic collection of pest and disease related information for agroforestry, e.g., in a central database, and of the development of strategies for reducing pest and disease risks in agroforestry in cooperation with farmers is stressed.This revised version was published online in November 2005 with corrections to the Cover Date.     

Ecological benefits provided by alley cropping systems for production of woody biomass in the temperate region: a review

In temperate Europe alley cropping systems which integrate strips of short rotation coppices into conventional agricultural fields (ACS) are receiving increasing attention. These systems can be used for crops and woody biomass production at the same time, enabling farmers to diversify the provision of market goods. Adding trees into the agricultural land creates various additional benefits for the farmer and society, also known as ecosystem services. However, tree-crop interactions in the temperate region have not been adequately substantiated which is identified as a drawback to the practical implementation of such systems. In order to bridge this gap, the current paper aims to present a comprehensive overview of selected ecosystem services provided by agroforestry with focus on ACS in the temperate region. The literature indicates that compared with conventional agriculture ACS have the potential to increase carbon sequestration, improve soil fertility and generally optimize the utilization of resources. Furthermore, due to their structural flexibility, ACS may help to regulate water quality, enhance biodiversity, and increase the overall productivity. ACS are shown as suitable land use systems especially for marginal sites. Based on the available data collected, we conclude that ACS are advantageous compared to conventional agriculture in many aspects, and therefore suggest that they should be implemented at a larger scale in temperate regions.     

Assessment of small mammal diversity in coffee agroforestry in the Western Ghats,India

Coffee agroforestry is a conservation strategy that has shown promise to support the diversity of bird, bat, and insect communities, but few studies have focused on non-volant mammals in coffee farms. We assessed mammal diversity within coffee agroforestry systems in Kodagu, India and investigated the impacts of the non-native shade tree species, Grevillea robusta, on mammal diversity. Twenty farms, with varying amounts of G. robusta planted within the coffee farm, were sampled throughout three rainfall zones during the 4-month study period. We captured six species of small mammals, with indirect methods yielding an additional five species, totaling 11 mammal species. Contrary to current ecological thought, we found that increased amounts of G. robusta did not have a negative impact on either abundance or richness of mammals. Small mammal abundances were higher at farms with greater amounts of herbaceous ground cover and larger, mature shade trees, while small mammal species richness was found to increase with an increase in tree species richness as well as greater amounts of herbaceous ground cover. Additionally, small mammal abundance was higher at coffee farms closer to forested areas. Based on these findings, we suggest the maintenance or cultivation of shade tree richness, mature shade trees, and herbaceous ground cover within coffee farms and preservation of forested areas within the landscape to enhance coffee agroforestry habitat for non-volant mammals. We hope that these habitat requirements will be incorporated into conservation strategies for the promotion of biodiversity within coffee agroforestry systems.     

Agroforestry for ecosystem services and environmental benefits: an overview

Agroforestry systems are believed to provide a number of ecosystem services; however, until recently evidence in the agroforestry literature supporting these perceived benefits has been lacking. This special issue brings together a series of papers from around the globe to address recent findings on the ecosystem services and environmental benefits provided by agroforestry. As prelude to the special issue, this paper examines four major ecosystem services and environmental benefits of agroforestry: (1) carbon sequestration, (2) biodiversity conservation, (3) soil enrichment and (4) air and water quality. Past and present evidence clearly indicates that agroforestry, as part of a multifunctional working landscape, can be a viable land-use option that, in addition to alleviating poverty, offers a number of ecosystem services and environmental benefits. This realization should help promote agroforestry and its role as an integral part of a multifunctional working landscape the world over.     

Agroforestry Systems as Alternative Land-Use Options in the Arid Zone of Thal,Pakistan

Agroforestry offers unique opportunities for increasing biodiversity, preventing land degradation, and alleviating poverty, particularly in developing countries, but factors explaining the adoption by farmers are not well understood. A survey of 524 farm households was conducted in Bhakkar district of Punjab, Pakistan to study factors that determine the adoption of agroforestry on the sand dunes in the resource-deficient region of Thal. Two types of agroforestry systems were studied: intercropping and border cropping (also known as boundary or perimeter planting). Both agroforestry systems included irrigated cultivation of the timber trees Eucalyptus camaldulensis (local name: sufeda) and Tamarix aphylla (local name: sars) with wheat, chickpeas (Cicer arietinum) (local name: chana) or cluster beans (Cyamous tetragocalobe) (local name: guars). The majority of the farmers was in favour of intercropping and border cropping. Most farmers reported the protection of nearby crops from dust storms as the most important positive perception about both agroforestry systems. Age, education, and farm to market distance were significant determinants of agroforestry adoption. Older and less-educated farmers, with farms closer to markets were less likely to adopt tree planting or border cropping in Thal. In general, the agroforestry systems examined were more likely to be adopted by farmers who can wait 3–4 years for harvesting crop outputs, but not by poorer farmers who are totally dependent on subsistence agriculture and cannot afford the high initial cost of agroforestry establishment, nor can they wait for crop output for extended periods. Furthermore, the adoption of both agroforestry systems was more likely in remote marginal areas than in areas close to markets. To increase agroforestry adoption rates, government policies should strengthen farmers’ knowledge of every stage of agroforestry through extension services, focusing particularly among the prime prospects, i.e. farmers who will be most likely to adopt agroforestry. Once the prime prospects have adopted it, the older, less-educated, and poor farmers of the rural population can be also focused on to motivate adoption.     

Agroforestry and its application in amelioration of saline soils in eastern China coastal region

Some environmental problems, especially soil salinity hinder the regional sustainable development of eastern China coastal region. Salinity mainly comes from tide weave, seawater flooding and seawater intrusion. Over exploitation of groundwater,which is the result of unfitful land use systems, leads to seawater intrusion and salt concentration increase. Agroforestry systems can enrich soil fertility and prevent soil salinization, furthermore help maintain biodiversity and enhance productivity. For the intergrated multiple ecosystems the most critical issue is to select optimum tree species and rationally arrange these plants. The basics of this multiple ecosystem is that different plants will occupy variable ecological niches within an area, both in space and in soil depth.Shelterbelts and trees intercropping with agricultural crops are major types of the multiple ecosystem. Shelterbelts can reduce wind speed and consequently lessen evaporation and erosion of the soil, increase pasture growth by up to 60% on exposed sites, increase crop yields by up to 25%. Besides intercropping with jujube, other agroforestry multiple ecosystem such as forestry plus agriculture,forestry plus agriculture plus fishery, and forestry plus animal husbandry are the most appropriate ways to utilise land resource in this region.     

The effects of management and plant diversity on carbon storage in coffee agroforestry systems in Costa Rica

Agroforestry systems can mitigate greenhouse gas (GHG) emissions, conserve biodiversity and generate income. Whereas the provision of ecosystem services by agroforestry is well documented, the functional relationships between species composition, diversity and carbon (C)-storage remain uncertain. This study aimed to analyze the effects of management (conventional vs. organic), woody plant diversity and plant composition on aboveground and belowground C-storage in coffee agroforestry systems. It was expected that organic farms would store more C, and that an increase in plant diversity would enhance C-storage due to complementarity effects. Additionally, it was expected that steep slopes decrease C-storage as a result of topsoil erosion. Woody plants were identified on 1?ha plots within 14 coffee farms (7 conventional and 7 organic). C-stocks in trees, coffee plants and roots were estimated from allometric equations. C-stocks in litter and topsoil (0?C25?cm) were estimated by sampling. On average, farms stored 93?±?29?Mg?C?ha^?1. Soil organic carbon accounted for 69?% of total C. Total C-stocks were 43?% higher on organic farms than on conventional farms (P?<?0.05). Conventional and organic farms differed in vegetation structure, but not in species diversity. It was found that the combined effect of farm type, species richness, species composition and slope explained 83?% of the variation in total C-storage across all farms (P?<?0.001). Coffee agroforestry in general and organic farms in particular may contribute to GHG mitigation and biodiversity conservation in a synergistic manner which has implications for the effective allocation of resources for conservation and climate change mitigation strategies in the agricultural sector.     

Agroforestry opportunities for the United States of America

Agriculture in the United States makes intensive use of large portions, of the nation's arable landscape. This landscape is dominated by large fields of annual crops with few perennial buffering communities within them. Agroforestry systems such as riparian buffers, alleycropping, windbreaks, tree/pasture systems, and forest farming provide buffering opportunities within these landscapes. Riparian buffers and alleycropping systems provide two unique opportunities toward sustainable production by reducing nonpoint source pollution while increasing ecological diversity. The major impediment to agroforestry in the United States is a lack of identity. Agroforestry as a practice is not officially recognized by federal and most state agencies and thus does not qualify for cost-share support or funding for research and establishment of demonstrations. A recent white paper, prepared by representatives from government agencies, academic institutions, and nongovernment organizations, identified eight major actions that could provide the support, for making agroforestry an acceptable alternative to nonsustainable agriculture. Ames, Iowa. Project No. 3209.Journal paper no. J-16071 of the Iowa Agriculture and Home Economics Experiement Station, Ames, Iowa. Project No. 3209.