A life-cycle assessment (LCA) was carried out to compare the environmental performance of different organic cropping systems with and without digestion of slurry and crop residues. The aims of the present study are: (1) to compare the environmental performance of organic farming dairy systems with the currently prevalent animal housing systems [solid farmyard manure (FYM) versus liquid slurry] as the main reference systems; (2) to analyze the effect of the implementation of a biogas digestion system on the consumption of fossil fuels and production of electrical energy; (3) to quantify the effects of the implementation of a biogas digestion system on the environment; and (4) to compare the obtained net energy yields with other means of obtaining energy by using the farmland area. The considered impact categories are greenhouse gas (GHG) balances, acidification, eutrophication and groundwater pollution. LCA results indicated that total emissions in systems based on FYM are much higher than in liquid slurry systems for most of the considered impact categories. The benefits of digestion of stable wastes in comparison with the reference system without digestion are mainly (1) the net reduction of the emissions of GHG and (2) energy recovery from produced biogas, while the disadvantages can be higher emissions of NH3 after spreading. The effects of additional biogas digestion of biomass such as crop residues (e.g., straw of peas and cereals) and cover crops are: (1) an optimization of the N-cycle and therewith higher yields; (2) higher energy production per unit arable land; (3) a further reduction of the GHG balance; but (4) higher N-related environmental burdens like eutrophication and acidification. The offsets of fossil fuel emissions were the largest GHG sink in most of the biogas digestion systems. The inclusion of a biogas plant into organic cropping systems and the use of the available wastes for production of energy largely increased the overall productivity of the farming system and matched very well the basic principles of organic farming such as a high self-sufficiency of the cropping system and reducing as much as possible the environmental impact of farming.

Supported by policy-makers and non-governmental organizations (NGOs), coffee farmer organizations obtain organic and Fairtrade certifications to upgrade their coffee and, thus, increase returns to their members. Whether this and other upgrading strategies fit into the business model of the cooperative and lead to success are often not considered. This research aims to identify similarities and differences between conventional and certified cooperatives and the resultant impact on farmers' incomes. We analyze the business models, upgrading strategies, and strengths, weaknesses, opportunities and threats (SWOT) of seven conventional, organic and Organic-Fairtrade certified coffee cooperatives and link these to members' coffee gross margins. We use data from over 100 in-depth qualitative interviews and a household survey of 327 cooperative members in northern Nicaragua. Results indicate that cooperatives often apply the same upgrading strategies despite very different business models and SWOT. There are also many commonalities of SWOT among cooperatives but no clear-cut differences between conventional, organic and Organic-Fairtrade certified cooperatives. The qualitative comparison of coffee gross margins among the cooperatives shows no clear income effect from participating in certified coffee production and certified cooperatives. It indicates, rather, dependence of gross margins on yield levels, the business model and upgrading strategies of the cooperatives. Upgrading through certification seems only successful with a suitable business model and other upgrading strategies. Policies should focus on (i) increasing as well as stabilizing coffee yields, and (ii) on the institutional framework of cooperatives by offering strategic support, credit access, external auditing of cooperatives and the establishment of a functional national coffee institute.

Many rangelands of the world are fire dependent and display a strong interaction between fire and grazing on animal behavior, productivity and ecosystem processes. The application of this fire–grazing interaction as patch-burn grazing (PBG) has recently been promoted in North America to conserve biodiversity and as an alternative for livestock management in fire-prone ecosystems to enhance forage quality and other production benefits. PBG is functionally applied by burning spatially and temporally discrete patches to allow livestock to choose where and when to graze. However, considering that the primary intent of PBG in fire-dependent ecosystems has been for the conservation of biodiversity, we synthesized the peer-reviewed literature to assess PBG as an alternative strategy for livestock management in fire-prone ecosystems. We reviewed the literature to assess PBG as an alternative livestock management approach to optimize animal production and conserve biodiversity in fire-prone ecosystems. We reviewed the results of 83 studies that focused on two main areas: (1) livestock production and inputs and (2) maintaining or improving ecosystem functioning and biodiversity to support sustainable livestock production. PBG can optimize cattle production by offsetting input costs such as supplemental feed, insecticides, herbicides, mechanical brush control, veterinary costs and cross-fencing. PBG can also maintain native herbaceous plant communities that are the resource base for cattle grazing enterprises by reducing woody plant encroachment, stimulating above- and below-ground biomass of native perennial grasses, enhancing nutrient cycling and optimizing plant diversity. PBG creates a habitat mosaic critical for many trophic levels of wildlife, particularly grassland birds, which are currently in decline. Further research is needed to clarify the potential environmental gradients defining applicability of PBG, economic outcomes of PBG, potential gastro-intestinal parasite control with PBG and other metrics of animal production. Overall, PBG is a viable management approach to improve productivity and biodiversity in fire-regulated grassland ecosystems in a manner supported by both fire and grazing disturbances. This is especially true when these communities have other organisms that depend on periodic disturbance and interaction with large animal grazing and is supported by ample empirical research.

The extension of agroecology requires an alternative extension pedagogy. Agroecology is more than merely the promotion of new technologies or practices, but rather a fresh understanding of how to optimize the configuration of biological and technological components of farming systems informed by ecological principles. This necessarily requires a shift in roles among growers and extensionists so that they can actively participate in networks of social learning. Agro-environmental partnerships have emerged in California as the primary strategy for extending alternative, agroecological knowledge in conventional agriculture. Partnerships are an intentional, multi-year relationship among at least growers, a growers' organization, and one or more scientists to extend agroecological knowledge and protect natural resources through a field-scale demonstration. Partnerships have been particularly successful in perennial crop farming systems, and have played critical roles in helping California's almond and pear growers to reduce organophosphate use by over 75%. This study provides a cross partnership comparison of grower participation in partnerships and proposes a five-part typology to rank this.

Overwintered cover crops mechanically terminated into mulch can be a weed management tool for reduced-tillage organic agriculture. However, the impacts of management options for cover cropping are not well understood, including cover crop variety, termination timing and termination method. In a field experiment, conducted in 2012 and 2013 in Western Washington, we examined three grains, four vetches and one barley–vetch mix terminated with two mechanical methods and at two different times. We determined the influence of cover crop variety and termination time on cover crop biomass production and tissue nitrogen (N), effectiveness of cover crop termination, soil nitrate–N and percent weed cover. We also determined the influence of termination method on percent weed cover. Cover crop biomass ranged between 3 and 9 Mg ha−1 and was not influenced by termination time; the greatest production was from three varieties of grain. Rye varieties were more effectively terminated with a roller–crimper than barley. Mean soil nitrate–N levels ranged from 1.9 to 18 mg kg−1 and were the greatest with vetches. Post-termination weed cover was greater in 2013 than in 2012 and the cover crop variety influenced weed cover at the Late termination time only. Neither plant N concentration in the cover crop mulch nor soil nitrate influenced weed cover. The results of this study indicate that cover crop biomass and termination timing are important factors influencing weed cover and termination effectiveness in cover crop mulch.

In the US farmers often market pastured poultry eggs for a premium price, claiming animal and human health benefits. We examined how moving pastured hens to forage legumes or mixed grasses influenced hen (Gallus gallus L.) egg omega-3 fatty acids and concentrations of vitamins A and E. We also compared the eggs of the pastured hens to those of hens fed a commercial diet in cages. We used a cross-over design to compare pasture species: 75 sister hens were assigned to one of three pasture treatment groups: (1) alfalfa (Medicago sativa L.), (2) red and white clover (Trifolium pretense L. and Trifolium repens L.) or (3) mixed cool season grasses. Groups were rotated to all three pasture treatments, each for 2 weeks and supplemented with 70 g commercial hen mash bird−1 day−1. Pasture botanical composition, forage mass, leaf to total ratio and plant fatty acid composition were compared among pasture treatments. Eggs of the pastured hens were compared to eggs of 50 sister hens that were fed only commercial hen mash in cages for the entire 6 weeks. Forage parameters varied somewhat, but did not explain plant linolenic acid variation. Seventeen of the 18 quantified egg fatty acids, and vitamin A concentrations did not (P<0.05) differ among the three pasture treatment groups. Eggs of the hens that foraged grasses had 23% more (P<0.0001) vitamin E than eggs of hens that foraged clover. Compared to eggs of the caged hens, pastured hens' eggs had twice as much vitamin E and long-chain omega-3 fats, 2.5-fold more total omega-3 fatty acids, and less than half the ratio of omega-6:omega-3 fatty acids (P<0.0001). Vitamin A concentration was 38% higher (P<0.05) in the pastured hens' eggs than in the caged hens' eggs, but total vitamin A per egg did not differ. At the end of the experiment, pastured hens weighed 14% less and averaged 15% lower hen-day egg production than caged birds (P<0.0001). Results suggest that grass pastures may enhance vitamin E in eggs of pastured hens more than clover, and pastured hens supplemented with commercial mash will produce eggs with significantly more vitamin E and total omega-3 fatty acids compared to eggs from caged hens fed only commercial hen mash. Pastured hens may have lower body weight and egg production than caged hens, unless they are supplemented adequately to meet their dietary energy and crude protein needs.

Agricultural expansion contributes to the degradation of biodiverse ecosystems and the services these systems provide. Expansion of urban and peri-urban agriculture (UPA), on the other hand, may hold promise to both expand the portfolio of ecosystem services (ES) available in built environments, where ES are typically low and to reduce pressure to convert sensitive non-urban, non-agricultural ecosystems to agriculture. However, few data are available to support these hypotheses. Here we review and summarize the research conducted on UPA from 320 peer-reviewed papers published between 2000 and 2014. Specifically, we explored the availability of data regarding UPA's impact on ES and disservices. We also assessed the literature for evidence that UPA can contribute to land sparing. We find that the growth in UPA research over this time period points to the emerging recognition of the potential role that UPA systems play in food production worldwide. However, few studies (n = 15) place UPA in the context of ES, and no studies in our review explicitly quantify the land sparing potential of UPA. Additionally, while few studies (n = 19) quantify production potential of UPA, data that are necessary to accurately quantify the role these systems can play in land sparing, our rough estimates suggest that agricultural extensification into the world's urban environments via UPA could spare an area approximately twice the size of the US state of Massachusetts. Expanding future UPA research to include quantification of ES and functions would shed light on the ecological tradeoffs associated with agricultural production in the built environment. As food demand increases and urban populations continue to grow, it will be critical to better understand the role urban environments can play in global agricultural production and ecosystem preservation.

Biogas digesters convert waste matter into a natural gas-like fuel and a nutrient-rich digestate by-product. This digestate has the potential to be used as a soil amendment to benefit crop production with or without biochar, a purported nutrient sponge. In a greenhouse study of several crop species, the effects of digestate fertilization on crop growth, photosynthetic efficiency, vegetable production and chemical nutrient levels were tested. Results indicate that increasing potency of the applied digestate fosters higher growth and fruit production rates of several studied plants but to a lesser degree than a conventional fertilizer. More potent digestate application increases antioxidant capacity, total phenolics content and ascorbic acid levels in kale compared to the control chemical fertilizer test groups but has confounding results on legume nutrient levels. Additionally, the combined application of biochar and biogas digestate added to compost and used as potting media positively impacts crop germination. This work has relevance to agrarian communities that could benefit from recycling livestock and food waste into fuel and a renewable fertilizer.

This article illuminates the geographic concept of ‘place’ in local foods. Because the social aspects of local food have been more fully addressed in previous literature, this review focuses instead on the ecological aspects of farming and food. First, the literature on natural resource use in agriculture provides contextual understanding of water use, biodiversity, soils and agro-ecological methods. The complex relationship between climate change and agriculture is described and models assessing the impacts of climate change on agriculture are detailed. The geography of local food is specifically addressed by describing methods for assessing natural resource use in local food, including food miles, consumer transportation, scale and community, agricultural methods and diet. Finally, future research paths are suggested to provide a comprehensive evaluation of the environmental impact of local food. Such research would encompass the geography of local food through development of broader, more inclusive strategy, including the concept of the ‘ecological appetite’ of crops and foods, the union of both social and ecological aspects of resource use, the linkages between rural and urban producers and consumers and the inclusion of farmers’ ecological knowledge. Overall, the geography of local food seeks to assess the where of food production and consumption, while incorporating key issues of how (agro-ecological methods benefiting the community) and what (locally appropriate crops).

Organic cropping systems that utilize winter grown cereal–legume cover crop mixtures can increase plant available nitrogen (N) to a subsequent cash crop, but the rate of N release is uncertain due to variations in residue composition and environmental conditions. A study was conducted to evaluate N availability from rye (Secale cereale L.)–hairy vetch (Vicia villosa Roth) cover crop mixtures and to measure the response of organically grown sweet corn (Zea mays L.) to N provided by cover crop mixtures. Nitrogen availability from pure rye, pure hairy vetch, and rye–vetch mixtures was estimated using laboratory incubation with controlled temperature and soil moisture. Sweet corn N response was determined in a 2-year field experiment in western Washington with three cover crop treatments as main plots (50:50 rye–vetch seed mixture planted mid September, planted early October, and none) and four feather meal N rates as subplots (0, 56, 112 and 168 kg available N ha−1). Pure hairy vetch and a 75% rye–25% hairy vetch biomass mixture (R75V25) released similar amounts of N over 70 days in the laboratory incubation. But, the initial release of N from the (R75V25) treatment was nearly 70% lower, which may result in N release that is better timed with crop uptake. Cover crops in the field were dominated by rye and contained 34–76 kg ha−1 total N with C:N ranging from 18 to 27. Although time of planting and management of cover crop quality improved N uptake in sweet corn, cover crops provided only supplemental plant available N in this system.

Kernza® intermediate wheatgrass (Thinopyrum intermedium) is a novel perennial grain and forage crop with the potential to provide multiple ecosystem services, which recently became commercially available to farmers in the USA. The viability and further expansion of this promising crop require understanding how it may fit the needs of farmers’ livelihoods and the structure of their farming systems. However, no prior research has studied the perceptions and experiences of Kernza growers. The goals of this research were to understand why farmers grow Kernza, how Kernza fits into their systems and identify challenges for future research. We conducted in-depth interviews with ten growers in the North Central USA during the summer of 2017, who accounted for a third of the Kernza farmers in the USA at the time. All farmers had a positive attitude toward experimentation and trying new practices, and they were interested in Kernza for its simultaneous ecological and economic benefits. Kernza was marginal in terms of area, quality of fields and resources allocated in the farm systems, which also meant that farmers maintained low costs and risks. Growers utilized and valued Kernza as a dual-use crop (grain and forage), sometimes not harvesting grain but almost always grazing or harvesting hay and straw for bedding. Weeds were perceived as a challenge in some cases, but Kernza was valued as a highly weed-suppressive crop in others. Farmers requested information on optimal establishment practices, assessment of forage nutritive value, how to maintain grain yields over years, weed management, markets and economic assessment of Kernza systems. These results agree with other cases on sustainable practices adoption showing that engaging farmers in the research process from the beginning, identifying knowledge gaps and testing management alternatives are critical for the success and expansion of novel agricultural technologies.

Despite an overall growth rate of the organic farming sector in the European Union, a considerable number of farmers cease organic production each year. Given the commitment of many European governments to increase the size of their organic farming sectors, reducing the rate of withdrawals from organic production may be an easier option than attracting new farmers into organic farming. In order to reduce the rate of withdrawals, knowledge about those farmers is required. However, to date, little is known about farmers who adopt and subsequently abandon organic farming. This study attempts to fill this gap in the literature by comparing and contrasting the farm and personal characteristics of organic, former organic and conventional farmers. To this end, primary data from 596 Irish cattle and sheep farmers are utilized. Overall, the findings reveal significant differences between the three groups. More specifically, organic farmers are found to be the most environmentally aware farmers, who also rate information gathering as more important than the remaining two groups. Organic farmers are younger, better educated and more likely to be women than conventional farmers. Former organic farmers stand out to be the least risk averse group and also express lower environmental awareness than organic farmers. Conventional farmers are found to be the most profit oriented and least environmentally aware group. In addition, this group farms more intensely stocked enterprises than the remaining groups. The paper concludes with a discussion of some policy recommendations aimed at increasing the size of the organic sector.

Information is needed on the role of cover crops as a weed control alternative due to the high adoption of conservation tillage in soybean [Glycine max (L.) Merr.] production. Field experiments were conducted from fall 1994 through fall 1997 in Alabama to evaluate three winter cereal cover crops in a high-residue conservation-tillage, soybean production system. Black oat (Avena strigosa Schreb.), rye (Secale cereale L.), and wheat (Triticum aestivum L.) were evaluated for their weed-suppressive characteristics compared to a winter fallow system. Three herbicide systems were utilized: no herbicide, a mixture of two pre-emergence (PRE) herbicides, or PRE plus post-emergence (POST) herbicides. The PRE system contained pendimethalin plus metribuzin. The PRE plus POST system contained pendimethalin plus a prepackage of metribuzin and chlorimuron ethyl applied PRE, followed by an additional chlorimuron ethyl POST application. No cover crop was effective in controlling weeds without a herbicide. However, when black oat or rye was utilized with only PRE herbicides, weed control was similar to the PRE plus POST input system. Thus, herbicide reductions may be attained by utilizing cover crops that provide weed suppression. Rye and black oat provided more effective weed control in the PRE only herbicide input system than wheat in conservation-tillage soybean. The winter fallow, PRE plus POST herbicide input system yielded significantly less soybean one out of three years when compared to systems that included a winter cover crop.

Perennial cropping systems may achieve significant improvement over annual systems in the synchrony between crop nutrient demands and nutrient supplies. Improvements in nutrient synchrony would result in the reduction of nutrient losses and their associated environmental impacts. A perennial system with high levels of synchrony would also require fewer nutrient inputs, such that it may be possible to develop an agriculture that functions mostly, if not entirely, on nutrient inputs from endogenous sources (i.e., weathering of primary and secondary minerals and biological nitrogen fixation). In this paper I describe three realms of research that will inform the development of relatively high-yielding grain production systems grown on endogenous nutrient supplies: (1) improvement of nutrient synchrony through the development of perennial crops; (2) identification of soils that are in a high nutrient release phase of pedogenesis, which could balance the export of rock-derived nutrients in crop harvests; and (3) optimization of legume density, harvest index and percent nitrogen derived from the atmosphere (%Ndfa) to achieve adequate nitrogen inputs through biological fixation.

Over the past 10 years, the organic sector has expanded continuously in Europe due to policy support and a growing market demand for organic products. In line with this development, many farmers converted to organic farming each year. Nevertheless, the total number of organic farms has not increased constantly in Europe. In several countries, the absolute number of organic farms actually decreased in some years of the past decade. Some of the deregistered farmers gave up completely; others reverted to conventional agriculture. Against this background, this article aims (i) to give an overview of the extent of reversion to conventional agriculture in Europe based on statistics, (ii) to conceptualize the decision to revert in the form of a theoretical model, (iii) to compare farmers’ reasons to revert to conventional farming based on existing studies, and (iv) to identify further research needs. The importance of reversions to conventional agriculture is difficult to determine with the existing data, especially as in most cases it is not recorded as to what happened to the farms after deregistering from organic certification. The data nevertheless show that there are large fluctuations in the organic sector with many farmers entering and exiting each year. In order to reveal the farmers’ reasons for deregistering, various qualitative as well as quantitative surveys have been carried out already. For most farmers, the decision to revert is a result of different factors. Reasons for the reversion of their farms can be classified into economic motives, difficulties regarding certification and control, problems with organic production techniques as well as the farms’ macro environment. In most cases, however, economic reasons played a main role. Suggestions for organic legislation bodies, advisory services and policy makers are derived out of the findings. A deeper understanding of the influencing aspects regarding reversions and the necessary changes in the organic sector to avoid them should be an important objective of forthcoming research.

In most developing countries, there has been a long-standing conflict of interest between using land for agriculture and the conservation of biodiversity. This paper reports on a study of factors influencing farmers’ decisions to integrate trees into their agricultural practice. We also discuss the possibility of protecting and managing planted and naturally regenerating trees on farmland in order to restore degraded land and improve biodiversity. Data were collected from interviews with farmers in the Center-West region of Burkina Faso and analyzed using Principal Component Analysis, multiple linear regression and binary logistic regression. The results show that farmers’ decisions to incorporate trees into their farmland were mainly influenced by silvicultural knowledge and skills, participation in farmers’ groups or other social organizations with an interest in tree conservation, the social value of biodiversity in the rural landscape, and the perceived economic benefits of trees on farmland. The most important factors associated with variation in levels of motivation to conserve trees on farms included household wealth, gender, age, education level, marital status, residence status, farmland size, household size and technical support. We conclude that an agroforestry project will be more successful if the local biophysical conditions and diversity of smallholder socio-economic characteristics and their perceptions, needs and preferences are considered in its design. There is also an immediate need for coordinated development of information and training to raise local community awareness of the potential of agroforestry as well as to disseminate information about adding value to tree products in order to encourage farmers to protect on-farm trees.

Modern agriculture relies heavily on fossil energy for food production. Reducing fossil energy and replacing that energy with renewable energy is critical in attaining a sustainable food system. Hand-scale intensive food production offers a reduction in fossil energy and an increased use of renewable human-based energy. Using biointensive production techniques, onions (Allium cepa) were grown in Pennsylvania, USA. A life-cycle analysis was performed to monitor energy utilization. Individual human labor tasks were evaluated using the factor method. This method accounts for the type and duration of physical activity. The average yield of eight onion varieties utilizing biointensive production in standard-sized beds (9.3 m2;100 ft2) was 160.2 kg. The US average for mechanical onion production is 46.1 kg/9.3 m2 (100 ft2). The energy efficiency ratio, specific energy and energy productivity were 51.5, 0.03 MJ kg−1 and 32.2 kg MJ−1 (MJ=megajoule), respectively. When defined within common boundaries, these three relationships: energy input, energy output and yield productivity allow researchers, farmers and policy-makers to select production systems and/or practices that better manage fossil and renewable energy for food production. Current mechanized agriculture has an energy efficiency ratio of 0.9. With most energy being supplied by fossil fuels. The energy efficiency for biointensive production of onions in our study was over 50 times higher than this value (51.5) and 83% of the total energy required is renewable energy. Biointensive production offers a viable energy use alternative to current production practices and may contribute to a more sustainable food system.

Greater London has a vibrant food scene comprising of many different types of urban and peri-urban ‘short food supply chains’ (SFSCs). This paper reports on exploratory research, which used examples of SFSCs from London to build a more detailed understanding of different types of urban SFSC and their relative performance compared to each other. To do this, we undertook a participatory sustainability impact assessment (SIA) in which local food system stakeholders were asked to rank the perceived impacts of five different urban and peri-urban SFSCs compared with the current ‘mainstream’ food supply system (defined as supermarkets retailing mass-produced, standardized food products). The SFSCs ranked were: (1) urban gardening (self-supply), (2) urban gardening (commercial), (3) community supported agriculture (CSA), (4) direct sale (on-farm) and (5) direct sale (off-farm). Results from the SIA showed that CSAs were regarded as delivering the highest overall social, economic and environmental benefits, followed by urban gardening (commercial), urban gardening (self-supply) and direct sales (off-farm). The lowest overall rating was for the supply chain direct sales (on-farm). All five SFSCs were ranked highest on the social aspects of sustainability. Following the participatory SIA of perceived sustainability, we next developed a questionnaire in order to test the feasibility of measuring the specific (rather than ‘perceived’) impacts of an urban SFSC. We applied the test at a community-led local food market in South London, where we conducted face-to-face interviews with all market stallholders (18 respondents) and a random sample of consumers (51 respondents). Results from the community-led market were similar to those acquired at the SIA workshop, with greater agreement about the social benefits of the market, compared with economic and environmental impacts. The results also suggest that producers underestimated consumers’ willingness to share the risks that the producers face and we identify this as an important aspect for future research. The paper concludes with reflections on the strengths and weaknesses of the SIA methodology.

Interest in organic grain production is increasing in the United States but there is limited information regarding the economic performance of organic grain and forage production in the mid-Atlantic region. We present the results from enterprise budget analyses for individual crops and for complete rotations with and without organic price premiums for five cropping systems at the US Department of Agriculture–Agricultural Research Service (USDA–ARS) Beltsville Farming Systems Project (FSP) from 2000 to 2005. The FSP is a long-term cropping systems trial established in 1996 to evaluate the sustainability of organic and conventional grain crop production. The five FSP cropping systems include a conventional, three-year no-till corn (Zea mays L.)–rye (Secale cereale L.) cover crop/soybean (Glycine max (L.) Merr)–wheat (Triticum aestivum L.)/soybean rotation (no-till (NT)), a conventional, three-year chisel-till corn–rye/soybean–wheat/soybean rotation (chisel tillage (CT)), a two-year organic hairy vetch (Vicia villosa Roth)/corn–rye/soybean rotation (Org2), a three-year organic vetch/corn–rye/soybean–wheat rotation (Org3) and a four- to six-year organic corn–rye/soybean–wheat–red clover (Trifolium pratense L.)/orchard grass (Dactylis glomerata L.) or alfalfa (Medicago sativa L.) rotation (Org4+). Economic returns were calculated for rotations present from 2000 to 2005, which included some slight changes in crop rotation sequences due to weather conditions and management changes; additional analyses were conducted for 2000 to 2002 when all crops described above were present in all organic rotations. Production costs were, in general, greatest for CT, while those for the organic systems were lower than or similar to those for NT for all crops. Present value of net returns for individual crops and for full rotations were greater and risks were lower for NT than for CT. When price premiums for organic crops were included in the analysis, cumulative present value of net returns for organic systems (US$3933 to 5446 ha−1, 2000 to 2005; US$2653 to 2869 ha−1, 2000 to 2002) were always substantially greater than for the conventional systems (US$1309 to 1909 ha−1, 2000 to 2005; US$634 to 869 ha−1, 2000 to 2002). With price premiums, Org2 had greater net returns but also greater variability of returns and economic risk across all years than all other systems, primarily because economic success of this short rotation was highly dependent on the success of soybean, the crop with the highest returns. Soybean yield variability was high due to the impact of weather on the success of weed control in the organic systems. The longer, more diverse Org4+ rotation had the lowest variability of returns among organic systems and lower economic risk than Org2. With no organic price premiums, economic returns for corn and soybean in the organic systems were generally lower than those for the conventional systems due to lower grain yields in the organic systems. An exception to this pattern is that returns for corn in Org4+ were equal to or greater than those in NT in four of six years due to both lower production costs and greater revenue than for Org2 and Org3. With no organic premiums, present value of net returns for the full rotations was greatest for NT in 4 of 6 years and greatest for Org4+ the other 2 years, when returns for hay crops were high. Returns for individual crops and for full rotations were, in general, among the lowest and economic risk was, in general, among the highest for Org2 and Org3. Results indicate that Org4+, the longest and most diverse rotation, had the most stable economic returns among organic systems but that short-term returns could be greatest with Org2. This result likely explains, at least in part, why some organic farmers in the mid-Atlantic region, especially those recently converting to organic methods, have adopted this relatively short rotation. The greater stability of the longer rotation, by contrast, may explain why farmers who have used organic methods for longer periods of time tend to favor rotations that include perennial forages.