Agriculture in the US Corn Belt is under increasing pressure to produce greater quantities of food, feed and fuel, while better protecting environmental quality. Key environmental problems in this region include water contamination by nutrients and herbicides emitted from cropland, a lack of non-agricultural habitat to support diverse communities of native plants and animals, and a high level of dependence on petrochemical energy in the dominant cropping systems. In addition, projected changes in climate for this region, which include increases in the proportion of precipitation coming from extreme events could make soil and water conservation in existing cropping systems more difficult. To address these challenges we have conducted three cropping systems projects in central Iowa: the Marsden Farm Cropping Systems experiment, the Science-based Trials of Row-crops Integrated with Prairies (STRIPs) experiment, and the Comparison of Biofuel Systems (COBS) experiment. Results from these experiments indicate that (1) diversification of the dominant corn–soybean rotation with small grains and forage legumes can permit substantial reductions in agrichemical and fossil hydrocarbon use without compromising yields or profitability; (2) conversion of small amounts of cropland to prairie buffer strips can provide disproportionately large improvements in soil and water conservation, nutrient retention, and densities of native plants and birds; and (3) native perennial species can generate large amounts of biofuel feedstocks and offer environmental benefits relative to corn- and soybean-based systems, including greater carbon inputs to soil and large reductions in nitrogen emissions to drainage water. Increasing biodiversity through the strategic integration of perennial plant species can be a viable strategy for reducing reliance on purchased inputs and for increasing agroecosystem health and resilience in the US Corn Belt.

Conservation agricultural systems rely on three principles to enhance ecosystem services: (1) minimizing soil disturbance, (2) maximizing soil surface cover and (3) stimulating biological activity. In this paper, we explore the concept of diversity and its role in maximizing ecosystem services from managed grasslands and integrated agricultural systems (i.e., integrated crop–livestock–forage systems) at the field and farm level. We also examine trade-offs that may be involved in realizing greater ecosystem services. Previous research on livestock production systems, particularly in pastureland, has shown improvements in herbage productivity and reduced weed invasion with increased forage diversity but little response in terms of animal production. Managing forage diversity in pastureland requires new tools to guide the selection and placement of plant mixtures across a farm according to site suitability and the goals of the producer. Integrated agricultural systems embrace the concept of dynamic cropping systems, which incorporates a long-term strategy of annual crop sequencing that optimizes crop and soil use options to attain production, economic and resource conservation goals by using sound ecological management principles. Integrating dynamic cropping systems with livestock production increases the complexity of management, but also creates synergies among system components that may improve resilience and sustainability while fulfilling multiple ecosystem functions. Diversified conservation agricultural systems can sustain crop and livestock production and provide additional ecosystem services such as soil C storage, efficient nutrient cycling and conservation of biodiversity.

Ecosystem functions and services provided by soils depend on land use and management. The objective of this article is to review and synthesize relevant information on the impacts of no-till (NT) management of croplands on ecosystem functions and services. Sustainable management of soil through NT involves: (i) replacing what is removed, (ii) restoring what has been degraded, and (iii) minimizing on-site and off-site effects. Despite its merits, NT is adopted on merely ∼9% of the 1.5 billion ha of global arable land area. Soil's ecosystem services depend on the natural capital (soil organic matter and clay contents, soil depth and water retention capacity) and its management. Soil management in various agro-ecosystems to enhance food production has some trade-offs/disservices (i.e., decline in biodiversity, accelerated erosion and non-point source pollution), which must be minimized by further developing agricultural complexity to mimic natural ecosystems. However, adoption of NT accentuates many ecosystem services: carbon sequestration, biodiversity, elemental cycling, and resilience to natural and anthropogenic perturbations, all of which can affect food security. Links exist among diverse ecosystem services, such that managing one can adversely impact others. For example, increasing agronomic production can reduce biodiversity and deplete soil organic carbon (SOC), harvesting crop residues for cellulosic ethanol can reduce SOC, etc. Undervaluing ecosystem services can jeopardize finite soil resources and aggravate disservices. Adoption of recommended management practices can be promoted through payments for ecosystem services by a market-based approach so that risks of disservices and negative costs can be reduced either through direct economic incentives or as performance payments.

Nowadays, the maize weevil Sitophilus zeamais—Motsch 1855 is the most relevant pest found during storage of maize grains. Aiming at protecting the agricultural crops, high amounts of synthetic pesticides are used around the world. In this sense, this work aimed at evaluating the insecticidal and repellent effect of essential oil of Ocotea odorifera (Vellozo) Rohwer (Lauraceae) (O. odorifera (sassafras)) leaves against the maize weevil in maize grains. The essential oil's chemical composition showed that sassafras contains camphor (43%) and safrole (42%) as major compounds. Our results show that sassafras oil was insecticidal and repellent to maize weevil. About 100% mortality was achieved using a concentration of 0.32 μl cm−2, after 24 h of exposure. The LD50 value was 14.1 μl or 0.09 μl cm−2 and the study of the effect on insect mortality at the lethal doses (LD50) showed that after 72 h mortality was 100%. The values of the preference index varied from −0.39 (0.065 μl cm−2) to −0.63 (0.659 μl cm−2), demonstrating that the plant oil presents repellent activity. The repellency bioassay simulating small bins showed the repellent effect level from 0.64 (0.36 μl cm−3) to 0.94 (2.9 μl cm−3). The essential oil of sassafras presented insecticidal and repellency against maize weevil. Although from an economical point of view synthetic chemicals are still more frequently used as repellents, natural products (essential oils) have the potential to provide efficient and safer repellents for humans and the environment.

Consumer Food Co-operatives (co-ops) have provided consumers an alternative to corporate supermarkets and big-box stores since the 1960s. Producers seeking broader marketing opportunities often turn to co-ops. This study examines how, within alternative food networks (AFNs), co-ops play a role in the emergence of the Domestic Fair Trade (DFT) movement in the USA. The DFT movement is based on the idea that family farms and small- to mid-sized farms in the global north are facing many of the same pressures as producers in the global south. The Domestic Fair Trade Association (DFTA) in the USA is the umbrella organization for a variety of stakeholders. The DFTA seeks to ‘support family-scale farming, to reinforce farmer-led initiatives such as farmer co-operatives, and to bring these groups together with mission-based traders, retailers and concerned consumers to contribute to the movement for sustainable agriculture in North America’1. This study assessed five co-ops (through interviews and document analysis) to determine their experiences with integrating DFT into their business practices. The research reveals that DFT concepts are important to co-operative decision-makers, but they are faced with challenges when it comes to actually integrating DFT into their business model. Insight into stakeholder perceptions and professional-level DFT activities, indicates that co-ops will be a key factor in determining whether the DFT movement will succeed in the USA.

Agri-environmental schemes involving organic farming or set-aside management aim at promoting biodiversity and restoring ecosystem functioning in agrarian landscapes. Application of pesticides in these crop fields is strongly regulated facilitating the spread of weeds but also allowing for the establishment of endangered herbs and a variety of animals. Recent studies found gastropods and earthworms to be legitimate dispersers of seeds of wild plants. We assumed that both groups also play a significant role in the spread and establishment of wild plants within crop fields. Therefore, we are conducting a series of experiments in three different study systems on (1) the role of earthworms and gastropods as dispersers of rare herbs and weeds in an organic rye field in Germany, (2) the seed feeding behavior of gastropods of plants sown in fallow ground in Switzerland, and (3) weed dispersal in irrigated rice fields by golden apple snails in the Philippines.

Studies in India from the early to late 1990s found that rural youths and women played a predominant role in livestock farming. Even though many studies differ in the extent and nature of the contribution of youths and women in livestock farming, all acknowledge their roles and contribution. Livestock farming acts as a source of supplementary income to youths and women and provides increased nutritional security. New economic policies of the1990s have brought changes to the livestock farming community. This paper attempts to understand and describe the role of women and youths in livestock farming. The research methodology employed for the present study is ex post facto design, and includes semi-structured open-ended interviews, observation and conversations with key informants. The study has found that a change in the roles of women and the participation of youths in livestock farming has occurred, which could be detrimental to the well-being of rural family farmers.

Over the past century, agricultural landscapes worldwide have increasingly been managed for the primary purpose of producing food, while other diverse ecosystem services potentially available from these landscapes have often been undervalued and diminished. The incorporation of relatively small amounts of perennial vegetation in strategic locations within agricultural landscapes dominated by annual crops—or perennialization—creates an opportunity for enhancing the provision of a wide range of goods and services to society, such as water purification, hydrologic regulation, pollination services, control of pest and pathogen populations, diverse food and fuel products, and greater resilience to climate change and extreme disturbances, while at the same time improving the sustainability of food production. This paper synthesizes the current scientific theory and evidence for the role of perennial plants in balancing conservation with agricultural production, focusing on the Midwestern USA as a model system, while also drawing comparisons with other climatically diverse regions of the world. Particular emphasis is given to identifying promising opportunities for advancement and critical gaps in our knowledge related to purposefully integrating perennial vegetation into agroecosystems as a management tool for maximizing multiple benefits to society.

Anaerobic digestion of manure and crops provides the possibility of a combined production of renewable energy and organic fertilizer on organic farms and has been suggested as an option to improve sustainability of organic agriculture. In the present study, the consequences of implementation of anaerobic digestion and biogas production were analyzed on a 1000 ha model farm with combined dairy and cash crop production, representing organic agriculture in Denmark. The effects on crop rotation, nitrogen flows and losses, yield, energy balance and greenhouse gas (GHG) emissions were evaluated for four scenarios of biogas production on the farm. Animal manure was digested for biogas production in all scenarios and was supplemented with: (1) 100 ha grass–clover for biogas, (2) 100 ha maize for biogas, (3) 200 ha grass–clover for biogas and reduced number of livestock, and (4) 200 ha grass–clover for biogas, reduced number of livestock and import of biomass from cuttings made in ungrazed meadows. These four scenarios were compared with the current situation in organic agriculture in Denmark and to a situation where slurry from conventional agriculture is no longer imported. Implementation of anaerobic digestion changed the nitrogen flows on the farm by increasing the slurry nitrogen plant availability and introducing new nitrogen sources from legume-based energy crops or meadows. The amount of nitrogen available for application as fertilizer on the farm increased when grass–clover was used for biogas production, but decreased when maize was used. Since part of the area was used for biogas production, the total output of foodstuffs from the farm was decreased. Effects on GHG emissions and net energy production were assessed by use of the whole-farm model FarmGHG. A positive farm energy balance was obtained for all biogas scenarios, showing that biomass production for biogas on 10% of the farm area results in an energy surplus, provided that the heat from the electricity production is utilized. The energy surplus implies a displacement of fossil fuels and thereby reduced CO2 emission from the farm. Emissions of N2O were not affected substantially by biogas production. Total emissions of methane (CH4) were slightly decreased due to a 17–48% decrease in emissions from the manure store. Net GHG emission was reduced by 35–85% compared with the current situation in organic agriculture. It was concluded that production of biogas on organic farms holds the possibility for the farms to achieve a positive energy balance, provide self-sufficiency with organic fertilizer nitrogen, and reduce GHG emissions.

Organic grain cropping systems can enhance a number of ecosystem services compared with conventional tilled (CT) systems. Recent results from a limited number of long-term agricultural research (LTAR) studies suggest that organic grain cropping systems can also increase several ecosystem services relative to conventional no-till (NT) cropping systems: soil C sequestration and soil N fertility (N mineralization potential) can be greater while global warming potential (GWP) can be lower in organic systems that use animal manures and cover crops compared with conventional NT systems. However, soil erosion from organic systems and nitrous oxide (N2O, a greenhouse gas) emissions from manure-based organic systems appear to be greater than from conventional NT systems, though data are limited. Also, crop yields, on average, continue to be lower and labor requirements greater in organic than in both tilled and NT conventional systems. Ecosystem services provided by organic systems may be improved by expanding crop rotations to include greater crop phenological diversity, improving nutrient management, and reducing tillage intensity and frequency. More diverse crop rotations, especially those that include perennial forages, can reduce weed pressure, economic risk, soil erosion, N2O emissions, animal manure inputs, and soil P loading, while increasing grain yield and soil fertility. Side-dressing animal manures in organic systems may increase corn nitrogen use efficiency and also minimize animal manure inputs. Management practices that reduce tillage frequency and intensity in organic systems are being developed to reduce soil erosion and labor and energy needs. On-going research promises to further augment ecosystem services provided by organic grain cropping systems.

This paper develops the concept of ‘critical agrarianism’ to describe and advance the pursuit of land-based work as a means of realizing social justice and environmental sustainability. Encouraging new agrarianism to more carefully scrutinize its agenda, critical agrarianism celebrates the promise of a close working relationship with the natural world while insisting that a return to the land—per se—is insufficient. In the practice of linking people and land, past and present, critical agrarianism continually questions and reshapes the very category of agrarian, toward a more equitable and enduring prosperity. I revisit both canonical agrarian writing and its critics, pulling out ‘back-pocket tools’ that can keep critical agrarians on track in building our alternative futures. I then offer several case studies of critical agrarianism in practice, encouraging a move beyond idealized models of agrarian ties, toward an empirical account of who has actually been doing the work to put food on the table. Noting the historical gap between working the landscape and having a property or citizenship right, I call for an agrarianism in which practices—not land title—are the basis of material and social community. Furthermore, I suggest that agrarianism must extend its web outward rather than inward, forging connections to the work of land tenure reform, education, community development, immigrant advocacy and trade policy. To be a critical agrarian is not to preserve fixed social-natural ties, but rather to practice a powerfully open and dialogical engagement with the world and one another.

Stale seedbeds are used by organic growers to reduce weed populations prior to crop planting. Rye mulches, derived from mechanically killed (rolled and crimped) winter rye cover crops, can serve the same purpose for spring-planted organic crops. Both methods can also be employed by conventional growers who face looming problems with herbicide resistant weeds. The objective of this research was to compare these methods over 2 years in central Minnesota in terms of weed seedling emergence, populations, biomass and manual-weeding times, as well as stands and yields of short-season and full-season soybean varieties planted late, in mid June. Rye mulch greatly lowered both pre- and post-planting weed populations of common annual weeds, which substantially affected necessity for augmented weed control. For instance, the need for within-crop manual-weeding was low for soybean planted into rye mulch (0–6 h ha−1), but ranged from 15 to 66 h ha−1 of labor for soybean planted in stale seedbeds and augmented by inter-row cultivation. However, rye mulch lowered soybean yield potential by 800–1000 kg ha−1 compared with stale seedbeds in 1 of 2 years. With organic feed-grade soybean seed valued at $1 kg−1, conventional soybean seed at $0.5 kg−1, and labor for manual-weeding at $10 h−1, the use of rye mulch compared with stale seedbeds augmented by manual-weeding are equally rational choices for organic growers in central Minnesota (assuming labor is available for hand-weeding), but rye mulches probably would be a wise financial option for conventional growers compared with hand-weeding. Lastly, full-season soybean had higher yields than short-season soybean and probably represents a prudent selection in central Minnesota, regardless of the late planting date requirements for both the rye mulch and stale seedbed systems.

This study evaluated the most significant physical, chemical and biological soil properties from a group of organic olive farms located in a typical olive-growing area of Andalusia, Spain, after 5 or more years since the shift from conventional to organic farming, and compared soils with those in nearby undisturbed (U) natural areas. Two soil management systems implemented in these organic olive farms to control weeds, tillage (T), characterized by non-inverting-shallow tillage in spring, and mechanical mowing (M), were compared and evaluated against the U areas. Organic olive orchards showed similar productivity (average fruit yield of 3130 kg ha−1 yr−1) as the conventional, rain-fed olive groves in the same area, with no significant differences due to soil management systems. Soil properties in the olive orchards (i.e. texture, pH, organic carbon (C), organic nitrogen (N), C:N ratio, cation exchange capacity (CEC) and exchangeable potassium) were in the suitable range for olive farming in both soil managements, although organic C and N, saturated hydraulic conductivity and available water-holding capacity (AWC) of the soil were lower than in the U areas. A principal component analysis (PCA) for soil properties in topsoil (0–10 cm depth) distinguished the T from M olive orchards and U areas, and determined organic C and N as the most significant soil properties to characterize them. Average values of soil organic carbon (SOC) stocks for the surface layer (0–10 cm depth) were 18.6, 59.3 and 67.8 Mg ha−1, for T and M soil management systems and U areas, respectively. This indicates that the sustainability of organic olive orchards could be significantly improved by shifting to M soil management to decrease soil erosion and depletion of SOC.

Due to the collapse of the socialist systems in 1989, Cuba's government promoted a series of structural changes to deal with resource scarcity and to enhance agricultural productivity. The upcoming crisis triggered adaptation strategies and led to a large-scale transition process towards a more sustainable model of agriculture. Farmers' experiments have been an implicit part of this process. Nowadays, farmers' capacity to experiment is widely accepted among the scientific community. However, detailed descriptions of farmers' approaches to experimentation are scarce. In this study, we examine the topics, resources, sources, motives, methods and outcomes of farmers' experiments in Cuba. The research methods comprised semi-structured interviews with 72 Cuban farmers, field notes, participant observation and a research diary. Key informants and 34 expert interviews added important insights into analysis. The results reveal that farmers' experiments are an integral part of farming in Cuba. Most farmers reported realizing their own experiments on their farms. The use of locally available resources was a crucial element for farmers' experiments. The topics were related to the introduction of new plant species or varieties, plant production, mechanization, fertilization, plant protection and the introduction of new animal species. The farmers' own idea was the most important source for experimenting, followed by ideas offered by colleagues and family members. Increasing production, independence from external resources and improving farm management were the main motives for experimenting. More than half of the farmers started to experiment without detailed written or mental planning, but made some considerations about the experiment before starting. Some planned more in detail and a few farmers devised a written plan, draft or model. Starting on a small scale was a way to minimize risks. The experiments were mainly evaluated by observation and comparison. Only a few farmers took records of their experiments. The most important outcomes were higher production, food self-sufficiency, work easement, improved plant health, increased knowledge, higher working efficiency and better taste of products. Farmers' experiments are a means of learning and they enhance farmers' capacity to adapt to changing conditions.

Women are the fastest growing segment of farm operators in the United States, comprising approximately 14% of principal operators and 30% of all operators of the nation's 2.2 million farms. Although several studies have examined the adoption of conservation practices by farmers, no study of which we are aware has focused on the use of conservation practices among women farmers in the US. Therefore, in 2008, we conducted a survey of women farmers in the Northeast US to better understand their use of conservation practices, and how their use is affected by demographic and farm characteristics, and membership in agricultural organizations and networks. We examined the practices related to the type of agricultural organizations, including commodity producer organizations, general farm organizations, women's groups associated with general farm or commodity organizations, farm women's organizations, and sustainable/organic agriculture organizations. Over 85% of the 815 respondents belonged to at least one organization. The most common organizations reported were sustainable/organic agriculture organizations (53.5%) and general farm organizations (50.8%). About one-third of respondents belonged to commodity-based organizations. The states with organized women farmers' networks—Pennsylvania, Maine and Vermont—represented more than half of them. Members of women's and sustainable or organic agriculture organizations tended to be younger, have less farming experience, and to have received more formal agricultural education than did members of commodity-based, general farm and women's agricultural groups within general farm organizations. Our results indicate that organizational membership and participation provide critical networks that support and reinforce the use of conservation practices. Some practices were positively associated with one type of organization while negatively associated with others. For example, compost production/application, crop rotation, manure incorporation, and organic crop and livestock production are more likely among members of sustainable/organic agriculture organizations, but less likely among members of general farm organizations. The converse is true for integrated pest management (IPM) on crop farms. Specific conservation practices had unique sets of variables linked to their use, with farm products being the most frequent predictors. This research serves as a baseline to understand the array of conservation practices used by women farmers in the Northeast US, and some factors associated with their use. The results suggest the need for consideration of the applicability of existing adoption models for women farmers. As women tend to have diversified operations with multiple markets, educational and regulatory programs that attempt to reach women farmers may need to consider the specific types of farms they operate to best match practices to their situations and goals.