Tillage is decreasing globally due to recognized benefits of fuel savings and improved soil health in the absence of disturbance. However, a perceived inability to control weeds effectively and economically hinders no-till adoption in organic production systems in the Upper Midwest, USA. A strip-tillage (ST) strategy was explored as an intermediate approach to reducing fuel use and soil disturbance, and still controlling weeds. An 8-year comparison was made between two tillage approaches, one primarily using ST the other using a combination of conventional plow, disk and chisel tillage [conventional tillage (CT)]. Additionally, two rotation schemes were explored within each tillage system: a 2-year rotation (2y) of corn (Zea mays L.), and soybean (Glycine max [L.] Merr.) with a winter rye (Secale cereale L.) cover crop; and a 4-year rotation (4y) of corn, soybean, spring wheat (Triticum aestivum L.) underseeded with alfalfa (Medicago sativa L.), and a second year of alfalfa. These treatments resulted in comparison of four main management systems CT-2y, CT-4y, ST-2y and ST-4y, which also were managed under fertilized and non-fertilized conditions. Yields, whole system productivity (evaluated with potential gross returns), and weed seed densities (first 4 years) were measured. Across years, yields of corn, soybean and wheat were greater by 34% or more under CT than ST but alfalfa yields were the same. Within tillage strategies, corn yields were the same in 2y and 4y rotations, but soybean yields, only under ST, were 29% lower in the fertilized 4y than 2 yr rotation. In the ST-4y system yields of corn and soybean were the same in fertilized and non-fertilized treatments. Over the entire rotation, system productivity was highest in the fertilized CT-2y system, but the same among fertilized ST-4y, and non-fertilized ST-2y, ST-4y, and CT-4y systems. Over the first 4 years, total weed seed density increased comparatively more under ST than CT, and was negatively correlated to corn yields in fertilized CT systems and soybean yields in the fertilized ST-2y system. These results indicated ST compromised productivity, in part due to insufficient weed control, but also due to reduced nutrient availability. ST and diverse rotations may yet be viable options given that overall productivity of fertilized ST-2y and CT-4y systems was within 70% of that in the fertilized CT-2y system. Closing the yield gap between ST and CT would benefit from future research focused on organic weed and nutrient management, particularly for corn.

Cover crops are known to promote many aspects of soil and water quality, yet estimates find that in 2012 only 2.3% of the total agricultural lands in the Midwestern USA were using cover crops. Focus groups were conducted across the Corn Belt state of Iowa to better understand how farmers confront barriers to cover crop adoption in highly intensive agricultural production systems. Although much prior research has focused on analyzing factors that help predict cover crop use on farms, there is limited research on how farmers navigate and overcome field-level (e.g. proper planting of a cover crop) and structural barriers (e.g. market forces) associated with the use of cover crops. The results from the analysis of these conversations suggest that there is a complex dialectical relationship between farmers' individual management decisions and the broader agricultural context in the region that constrains their decisions. Farmers in these focus groups shared how they navigate complex management decisions within a generally homogenized agricultural and economic landscape that makes cover crop integration challenging. Many who joined the focus groups have found ways to overcome barriers and successfully integrate cover crops into their cropping systems. This is illustrated through farmers' descriptions of their ‘whole system’ approach to cover crops management, where they described how they prioritize the success of their cover crops by focusing on multiple aspects of management, including changes they have made to nutrient application and modifications to equipment. These producers also engage with farmer networks to gain strategies for overcoming management challenges associated with cover crops. Although many participants had successfully planted cover crops, they tended to believe that greater economic incentives and/or more diverse crop and livestock markets would be needed to spur more widespread adoption of the practice. Our results further illustrate how structural and field-level barriers constrain individual actions, as it is not simply the basic agronomic considerations (such as seeding and terminating cover crops) that pose a challenge to their use, but also the broader economic and market drivers that exist in agriculturally intensive systems. Our study provides evidence that reducing structural barriers to adoption may be necessary to increase the use of this conservation practice to reduce environmental impacts associated with intensive agricultural production.

Many states including California allow fruit and vegetable checks (FVCs) issued by the Women, Infants and Children (WIC) Program to be redeemed at farmers’ markets. Despite the potential of the FVC program to increase the revenue of participating farmers and to provide fresh, locally grown fruits and vegetables to WIC participants, analysis of data for California shows that redemptions of FVCs at farmers’ markets have to date been miniscule. We study the barriers to use of FVCs at farmers’ markets and consider strategies for expanding both farmer and WIC client participation in the farmers’ market program. Our methodology involved design, implementation and analysis of surveys of both farmers’ market managers and farmer vendors who participate in the program and analysis of the behavior of WIC participants through California WIC program redemption data. One major factor limiting redemptions in California is that relatively few farmers’ markets currently accept FVCs and both market managers and farmers report that the authorization process is onerous. WIC participants who shopped at authorized markets more fully utilized the fixed-dollar value of their voucher, compared with participants who shopped at other authorized WIC vendors. Nevertheless, participants who visited a farmers’ market are unlikely to return. The study concludes with suggested pathways to increase WIC participant utilization of farmers’ markets.

With the advent of confined feeding systems and associated herd size increases, dairy farms have had to import more feed from off the farm, leading to on farm nutrient surpluses. Management-intensive grazing (MIG) is an alternative to confined feeding. Under MIG, the herd is rotated among small paddocks every 12–24 h for efficient conversion of forage into milk using grass pasture to provide most of the herd's nutritional needs. Previous research on MIG reported high concentrations of nitrate under grassed monolith lysimeters and grazed pastures. However, because of the high levels of nitrogen (N) fertilization and ponding of cow urine in lysimeters, these previous studies may have overestimated nitrate leaching losses from MIG systems as practiced in the mid-Atlantic region. To determine the extent of nitrate losses to groundwater under MIG in the mid-Atlantic, we sampled shallow groundwater biweekly for 3 yrs on six watersheds in three Maryland dairy farms, one confined and two MIG-based farms. Transects of nested piezometers and ceramic tipped suction lysimeters were installed in each watershed. Seasonal mean nitrate-N concentrations under the four grazed watersheds were generally lower than under the confined feeding farm watersheds and were generally below the widely used drinking water standard of 10 mg L−1. Average nitrate-N concentrations for all four grazed watersheds were between 4 and 7 mg L−1, while the two confined feeding farm watersheds averaged 7 and 11 mg L−1, indicating that the MIG system did not cause excessive nitrate leaching.

Perennial grain crops are expected to sequester soil carbon (C) and improve soil health due to their large and extensive root systems. To examine the rate of initial soil C accumulation in a perennial grain crop, we compared soil under perennial intermediate wheatgrass (IWG) with that under annual winter wheat 4 years after the crops were first planted. In addition, we tested the effect of three nitrogen (N) sources on C pools: Low available N (Low N (Organic N); 90 kg N ha−1 poultry litter), moderately available N (Mid N; 90 kg N ha−1 urea) and high available N (High N; 135 kg N ha−1 urea). We measured aboveground C (grain + straw), and coarse and fine root C to a depth of 1 m. Particulate organic matter (POM-C), fractionated by size, was used to indicate labile and more stabilized soil C pools. At harvest, IWG had 1.9 times more straw C and up to 15 times more root C compared with wheat. There were no differences in the size of the large (6 mm–250 µm) or medium (250–53 µm) POM-C fractions between wheat and IWG (P > 0.05) in surface horizons (0–10 cm). Large POM-C under IWG ranged from 3.6 ± 0.3 to 4.0 ± 0.7 g C kg soil−1 across the three N rates, similar to wheat under which large POM-C ranged from 3.6 ± 1.4 to 4.7 ± 0.7 g C kg soil−1. Averaged across N level, medium POM-C was 11.1 ± 0.8 and 11.3 ± 0.7 g C kg soil−1 for IWG and wheat, respectively. Despite IWG's greater above and belowground biomass (to 70 cm), POM-C fractions in IWG and wheat were similar. Post-hoc power analysis revealed that in order to detect differences in the labile C pool at 0–10 cm with an acceptable power (~80%) a 15% difference would be required between wheat and IWG. This demonstrates that on sandy soils with low cation exchange capacity, perennial IWG will need to be in place for longer than 4 years in order to detect an accumulated soil C difference > 15%.

Cotton is an important source of income for smallholder farmers in India, usually grown very intensively. To counteract negative impacts of cotton cultivation in India, such as environmental degradation and financial dependency due to high input costs, organic cotton cultivation is being promoted by non-governmental organizations in the country. This study examines how the conversion to organic cotton cultivation influences the livelihood of smallholder farmers in rural India. Interviews with organic farmers were conducted in Odisha, India, complemented by expert interviews and observations in the field. Results show that farmers profit from organic agriculture, mainly due to soil improvements, through reduced exposure to toxic chemicals and lower input costs, which in turn reduces dependency on money lenders. Organic agriculture enables smallholder farmers in the study region to improve their livelihood by providing access to training and by organizing in groups. Important social impacts identified in this study were capacity building and strengthened communities, through training and institution building. However, a higher workload, due to the higher work intensity of organic farming practices, was also observed, with this impacting women more than men. Environmental conditions and gender aspects still remain challenging.

Agro-ecological service crops (ASC) can increase the vegetation complexity of agroecosystems leading to a positive impact on natural enemies of arthropod pests and on weed control. In this study, two ASC terminations (green manure and roller crimper) and a Mater-Bi-mulched control (MB) were compared in order to describe the effects on pests and beneficial dynamics in an organic vegetable system. The trials were conducted over two consecutive growing seasons in 2014 and 2015. Zucchini were grown as cash crop and barley as ASC. Pests and natural enemies were monitored fortnightly by visual samplings along the whole zucchini-growing season. Zucchini plants showed a faster vegetative growth in MB treatment than in ASC terminations. In both years, MB plots were characterized by higher soil temperature and higher leaf nitrogen concentration resulting in plants more susceptible to Aphis gossypii infestations. In all the experimental plots, natural enemies controlled aphid infestations and no insecticide and sprays were necessary. In conclusion, the tested ASC techniques have been suggested as a tool to mitigate aphid infestation.