Field studies were conducted in 1997 and 1999 to determine the effect of a broadcast-seeded glyphosate-tolerant/conventional soybean seed mix on soybean seed yield, gross profit margin from weed management, and early-season weed suppression prior to a single glyphosate application. Tests were established by broadcasting and incorporating 494,000 seeds/ha glyphosate-tolerant soybean in combination with 0 to 1,976,000 seeds/ha conventional soybean. Glyphosate at 1.12 kg ai/ha was applied at the V5 to V6 soybean growth stage to kill all conventional soybean plants and emerged weeds. The broadcast planting technique was effective in establishing a soybean stand on a silt loam but was ineffective on a silty clay soil. Hemp sesbania and pitted morningglory control, resulting from interference with soybean, were correlated with percent soybean groundcover (R 2 = 0.961 to 0.971) and population (R 2 = 0.821 to 0.860) at the V5 to V6 soybean growth stage. Although not significant, increased yield and gross profit margin of dryland soybean occurred as the total seeding rate of the seed mix increased from 494,000 to 741,000 seeds/ha. A dryland seeding rate of 741,000 compared to 494,000 seeds/ha resulted in 438 kg/ha and $93.78/ha increase in seed yield and gross profit margin, respectively. Interference between the two soybean cultivars at 1,976,000 seeds/ha reduced yield. Irrigated soybean at 988,000 seeds/ha produced the greatest seed yield and gross profit margin at 2,987 kg/ha and $555.86/ha, respectively. Maximum yields were attributed to early-season weed suppression.

Strategies for pesticide use reduction have suffered from limited adoption. The impact of such strategies will be greater if they appeal to farmers with typical demographics and attitudes. A participatory, on-farm study was conducted to assess the potential of Pesticide Free ProductionTM (PFP) [Pesticide Free ProductionTM and PFPTM are registered trademarks of the University of Manitoba.] to be widely implemented on mainstream farms in Manitoba, Canada. PFP is a flexible, simple framework intended to appeal broadly to farmers who may not have adopted other pesticide use reduction initiatives. It may also provide a marketable food product label. This novel crop production system prohibits the use of in-crop pesticides and seed treatments during one crop year, as well as prior use of residual pesticides. Applications of nonresidual pesticides (such as glyphosate) are permitted prior to crop emergence. Synthetic fertilizer use is permitted at any time. The objectives of this study were: (1) to determine if the demographic and attitudinal characteristics of farms and farmers participating in a PFP pilot project varied depending on the level of PFP implementation; and (2) to compare the characteristics of farms and farmers participating in the pilot project with standards representing average farms and farmers in Manitoba. A total of 71 farmers, representing 120 fields and 11 crops, participated in the study. Fields and farmers were categorized into three groups, based on whether or not fields: (1) achieved PFP certification status and (2) were in transition to organic production. There were few demographic differences among groups. Demographic characteristics of participating farmers were typical for Manitoba, with the exception that participating farmers who were not in transition to organic production had higher levels of education than a random sample of Manitoba farmers. Attitudinal orientation (adherence to a conventional versus an alternative agricultural paradigm) of participants who were not in transition to organic production was similar to that of a random sample of Manitoba farmers. Fields and farms on which PFP was implemented were relatively large in the context of Manitoba averages. Participants indicated high satisfaction with certifiable PFP crops and high levels of interest in implementing future PFP. Pesticide free production demonstrates significant potential for broad adoption in this region.

Environmental and social concerns about the use of capital-intensive agricultural technologies have fueled questions about the process, impact, and future direction of the system that is largely responsible for developing these technologies; that is, publicly funded agricultural research at U.S. land-grant universities. Although social scientists have analyzed the public agricultural research system and farmers' attitudes towards various capital-intensive agricultural technologies, there has been less research on farmers' attitudes toward publicly funded research that focuses specifically on lowerinput agricultural technologies that contribute to sustainability goals. This research examines farmers' attitudes toward publicly funded research on one such low-input technology, deep-bedded hoop structures for swine production. With lower capital costs and purported environmental and management advantages, hoop structures have been promoted to and adopted by growing numbers of Midwest swine producers. The study hypotheses draw on published theories of the treadmill of technology, and of innovation adoption and diffusion. Using a 1997 mail survey of Iowa swine producers (n = 298), we examined factors associated with producers' attitudes toward publicly funded research on hoop structures and found that 40% were supportive of the research, 40% were opposed, and 20% were undecided. Of the variables examined, the producer's assessment of hoop structures' contribution to sustainability, number of external knowledge sources about hoop structures, and formal education were each significantly related to support for publicly funded hoop-structure research. Two farm structure variables, marketings and percentage of income from farming, were not significantly related in this study. Future research on farmers' attitudes toward public sector agricultural research should take account of farmers' views of potential impacts of the specific technologies being researched and developed, and the nature of farmers' ties to the land-grant university system. This study clarifies the importance of farmers' perceptions and concerns about specific agricultural technologies in directing public agricultural research planning and policy toward broader sustainability goals.

Changes in soil physical and chemical properties following conversion from conventional to low-input farming systems could alter root growth in com and hence aboveground growth and yield. The main hypothesis we tested is that low-input and conventional farming systems produce different amounts of corn roots. We compared low-input and conventional farming systems, row position (row and interrow), and soil depth for effects on root length density in a Comly silt loam (Typic Fragiudalf) at the Rodale Institute Research Center in Kutztown, Pennsylvania. On all sampling dates studied (two each in 1989 and 1990) root length density under low-input farming systems was significantly greater than under conventional farming systems. We used analysis of covariance to correct for soil factors that could not be directly controlled. Soil water and bulk density had no clear effect on root length density. In contrast, there was significant covariance of soil organic matter with root length density on two of the four sample dates. Root networks were more dense in soil pockets rich in organic matter for every farming system, row position, and depth. These findings indicate that low-input farmers may be manipulating root production of corn to allow com to absorb more nutrients and water when water in the topsail is limited.

This paper explores the constraints to sustainable agriculture in the Com Belt stemming from the trend toward increased farm size and the continued dependence of the region on undifferentiated farm commodities produced for regional, national, and international markets. It is based on a three-county comparison of 14 full-time farmers who have embraced sustainable principles and practices, and a randomly sampled group of 25 farmers. An encouraging finding was the substantial progress made towards lower-input production of com and soybeans by the nine farmers who had adopted the ridge tillage system, which uses elevated seedbeds, banded herbicides, and post-plant nitrogen application to reduce both soil erosion and synthetic chemical inputs while maintaining yields. However, operators of large farms that depend on hired labor and highly dispersed field sites regarded these practices as too risky at their scale of production despite their short-term economic and long-term environmental benefits. The region's commercial farmers appear split between family farmers who wish to avoid the headaches of scale expansion and hired labor, and therefore, embrace more efficient low-input systems such as ridge tillage versus those who reject the increased management intensity and risks of lower-input systems in favor of scale expansion via more chemical-intensive no-till systems. Although ridge tillage represents movement toward low-input cash grain production, low-input production systems alone are not sufficient to improve the underlying social welfare of rural areas. Arresting the trend towards fewer and larger farms will also require development of more specialized or more localized markets for sustainably produced commodities.

Cuba's agriculture after the 1959 revolution had been based on large-scale, capital intensive monoculture, which made Cuba heavily dependent on the socialist bloc for subsidized agrichemical inputs and for set prices of agricultural exports. However, with the collapse of the Soviet Union and its Eastern European allies in 1989–90, Cuba's inputs of fertilizer, pesticides, and petroleum dropped by more than half Cuba responded with a dramatic shift in its agricultural development model that featured appropriate technology, alternative organization of labor, alternative planning, and environmental preservation. Cuban pest control efforts now focus on biological control and on enhanced monitoring and diagnostic techniques. Soil management emphasizes biofertilizers and vermiculture. Minimum tillage and crop rotation are frequent practices among Cuba's independent farmers, agricultural cooperatives, and state farms. The transition to low-input agriculture has decreased the exodus of people from rural areas to cities, and has lead to establishment of lab or camps with volunteer labor and long-term programs for rebuilding rural communities. To address the loss of important food imports while ensuring environmental conservation, agricultural planning now gives priority to crop rotations, city gardens, and introduction of food crops in sugar cane areas.

Crops grown in narrow rows (NR, 0.25 to 0.38 m) shade weed seedlings more than do those grown in traditional wide rows (WR, 0.76 m). NR crops may require less herbicide and interrow cultivation than WR crops for equally effective weed control. This hypothesis was tested by comparing weed control and crop yield in NR and WR crops when the following percentages of recommended application rates (RAR) of standard herbicides were applied: soybean, 0, 50 and 100%; sunflower, 0, 25, 50, and 100%; and corn, 0, 33, and 100% in three separate sets of experiments conducted over 2, 3, and 4 years, respectively. In all treatments with 100% RAR, excellent weed control prevented reductions in crop yield. When only 25 to 50% RAR was applied, weed control was consistently high in NR (82 to 99% control), but variable in WR (42 to 99% control). Weed control and crop yields typically were lowest in NR without herbicides. Interrow cultivation controlled 0 to 81% of weeds in WR crops. In reduced herbicide treatments (25 to 50% RAR), yields of NR soybean and sunflower typically were about equal to those in WR with 100% RAR, but NR corn yields were about 10% less. Considering the reduced herbicide use and lower weed control costs, planting corn, soybean, and sunflower in narrow rows may represent a practical form of low-input production of these important crops.

Adoption of agricultural practices that reduce or eliminate chemical use creates tradeoffs among yields and output, production costs and net income at the farm level. If widespread adoption is to occur, potential improvements in human health and the environment from reduced chemical use must be weighed against effects on aggregate farm income and consumer food prices. At present, these tradeoffs are subject to considerable debate.

I review available farm level and aggregate economic studies of reductions in total agricultural chemical use. At the farm level, available studies suggest that organic and low-input farming systems result in declines in per acre yields and in lower net returns than most conventional farming systems, although the studies do indicate that net returns for the two systems can be comparable under some conditions. Several studies suggest that low-input systems perform well with respect to risk criteria. I also discuss the potential influence of government programs on the profitability of some low-input farming systems.

All aggregate economic models conclude that widespread adoption of organic farming would result in decreased yields, decreased aggregate output, increased farm income, and large increases in consumer prices. These models have limitations, however. Recommendations are made for further economic research of the impacts of reducing agricultural chemical use at both the farm and aggregate levels.

Involvement of farmers in sustainable agricultural research can have important benefits, since farmers originated many sustainable agriculture innovations and can contribute a valuable perspective different from that of researchers. However, this does not mean, as is sometimes said, that all kinds of sustainable agricultural research necessarily should give farmers a major role—perhaps the dominant role—in choosing topics and overseeing the work. This belief overlooks the fact that farmers are just one of many groups that publicly supported research is supposed to serve and that their interests do not by themselves embody the full range of goals that sustainable agriculture tries to achieve. Moreover, although farmers can bring valuable insights to research, these alone will not be enough to insure that a sustainable agriculture research program has an appropriate mix of applied versus basic, short-term versus long-term, and component-level versus system-level studies.

The primary objectives of this study were to describe the various pest control and soil fertility management strategies used by North Carolina farmers and to characterize the types of farms and farmers using each strategy. In 1988, a survey was mailed to farmers who had shown interest in alternative methods and a randomly selected control group of conventional farmers. Cluster analysis on crops, inputs, and cultural practices used by crop farmers in the combined sample showed that they fall into three distinct groups. Very few members of the first group apply standard synthetic fertilizers and pesticides. Instead, more than three-quarters of them use cover crops, compost, organic mulch, commercial fertilizers and pesticides labeled as “organic”, resistant varieties, hand weeding, mechanical cultivation, scouting, and biological pest controls. More than half of the second group did not use any nutrient and pest management inputs or practices except synthetic fertilizers, herbicides, and lime. More than three-quarters of the third group reported use of synthetic fertilizers, synthetic herbicides, and lime, but also employed most of the cultural practices reported by alternative farmers. However, they less frequently used labor-intensive practices (such as manuring, mechanical cultivation, and hand weeding) and information-intensive practices (such as scouting and companion planting). Information sources, concerns about farm chemicals, and length of farming experience discriminated better than other socioeconomic factors and farm characteristics between farmers who use conventional chemical inputs and those who use alternative practices. Group 1 farmers differed from Group 3 farmers most sharply in that they rank the cost of pest control products and their extension agents' advice lower, have lower farm incomes, read more information sources promoting reduced synthetic chemicals, own more of the land they operate, and have less farming experience. The only factors significantly discriminating Groups 1 and 2 were that Group 1 fanners rank the importance of their extension agents' recommendations lower and effects of chemical products on birds and wildlife higher, read more reduced-chemical information sources, and have less farming experience.

Conventional agriculture is increasingly criticized as being too concentrated in ownership; too reliant on technology, petroleum-based inputs, and credit; too specialized and ecologically unsound; and too dependent on government subsidies. Alternative agriculture is offered by many as an alternative, and we discuss the possible impacts of its widespread adoption on farm income, yields, regions, labor, trade, environmental quality, and farm structure. The profitability of alternative agriculture is also examined - in so doing, a distinction is made between the adoption of low-input practices and a more holistic alternative agricultural system.