Excessive nitrogen fertilizer use in corn production has resulted in widespread nitrate pollution of ground water and economic losses for farmers. In addition, reliance on nitrogen fertilizers produced with large amounts of fossil fuels may not be economically or environmentally sustainable in the future. Although leaching of significant amounts of nitrate to the ground water is inherent in growing corn, several techniques are available for more environmentally and agronomically sound management. The following management practices are discussed in this article: sidedress as the main method of N fertilizer application; the pre-sidedress (Magdoff) nitrate soil test; farm-based nitrogen sources (manures, green manures, and rotations with sod crops); cover crops for lowering profile nitrate during the most likely period for leaching; and the end of season stalk nitrate test.

Raised field agriculture in southwest Tlaxcala, Mexico, is a sophisticated, intensive traditional system of wetland cultivation that dates back to as early as 300 B. C. It provides an exceptional example of how farming practices can fit into and even take advantage of ecosystem processes. The raised fields appear to be largely self-reliant in energy and nutrients. Tlaxcalan farmers use canals, aquatic plants, polycultures, alder (Alnus firmifolia) and other trees to intensify the nutrient input into their fields and minimize nutrient losses through leaching and runoff Although the raised field system is an impressive, functioning example of a historically sustainable farming system, it is endangered by modern pressures to increase production through higher use of inputs and alteration of agroecosystem design.

A mail survey of Iowa farmers with membership in the Practical Farmers of Iowa, a sustainable agriculture organization, was used to examine perceptions of institutional support for information on reducing chemical inputs, needed research for farming with sustainable practices, and policy needs for encouraging farmers to adopt sustainable practices. We first developed a chemical input index to measure commitment to sustainable practices and to analyze information sources and research and policy needs. Results indicate that sustainable farmers rely primarily on each other and on their personal experience for information about sustainable practices; they use conventional farm practice information sources considerably less. The primary research need identified by the respondents was for better nonchemical weed control. Other important research needs identified were: nonchemical insect control, new seed varieties, cover crops, alternative tillage methods, and the economics of sustainable systems. The primary policy needs identified were more information and educational programs about sustainable agriculture and increased taxes on farm chemical use. We discuss the implications of the relationship between institutional support and the adoption of sustainable agriculture practices.

A rapid reconnaissance survey (sondeo) of twenty-five western Oregon and Washington horticultural producers was conducted using interdisciplinary interviewing teams and flexible on-farm interviews. The group interviewed included both certified organic and conventional farmers who are adopting innovative production methods. Our objectives were to determine the primary factors affecting the choice of farming methods, to identify growers' responses to these factors, to examine the effectiveness of the sondeo technique for gathering such information, to build a team for the longer-term studies, and to locate growers to participate in the longer-term studies. The growers shared characteristics that crossed organic-conventional boundaries. Less experienced growers identified practical crop management issues as their primary problems, while the more experienced ones were concerned with labor and regulatory problems. Most conventional growers were reducing their reliance on agricultural chemicals; organic producers generally used fewer agricultural chemicals, but many relied on organically certified insecticides. A primary regulatory concern among conventional growers was the loss of pesticide registrations for minor crops. Both organic and conventional growers were concerned about government regulation of farm labor, particularly increased paperwork and changing immigration law. Many growers attempted to provide good working conditions to retain a reliable labor force, but a few are mechanizing the harvest to reduce labor requirements. They were aware of the increasing public interest in the health aspects of agricultural methods and were responding with modified chemical use, direct involvement in public education, and membership in commodity groups, cooperative marketing groups, and other grower organizations. The sondeo was a fast and low-cost method for gathering information and provided team members with an interdisciplinary perspective that will be valuable in future research.

Consumer cooperatives in Japan, which is by far the United States' largest overseas market for agricultural commodities, expanded rapidly in the 1980s. Their recent success, according to Japanese reports, has been due to their responsiveness to increasing consumer demand for foods produced with minimal use of petrochemical inputs. I present data that confirm this claim by showing that the high level of concern that Japanese consumer cooperative members have about food safety is the main reason they give for joining cooperatives. I then discuss the significance of this trend for American agriculture, in particular whether Japanese consumer cooperatives could become a marketing channel for Americans who specialize in producing food with less intensive use of agricultural chemicals.

In the past several years, researchers, educators, policymakers, and activists have initiated sustainable agriculture programs and efforts the world over. This development has sometimes been accompanied by a sense that it is time to stop discussing sustainability at a conceptual level and get on with the work of making agriculture sustainable. Our perspective is that it is critical to pursue a comprehensive definition of sustainability in order to set sustainable agriculture priorities and ensure that sustainable agriculture takes a path that does not reproduce problems of conventional agriculture. In this paper we briefly review some popular definitions of sustainable agriculture and find that their focus is primarily on farm-level resource conservation and profitability as the main components of sustainability. Others have challenged this approach for either not examining the social aspects of sustainability or for containing an implicit assumption that working on the environmental, production, and microeconomic aspects of sustainability will automatically take care of its social aspects. We propose an expanded conceptualization of sustainability—one that focuses on the entire food and agriculture system at a global level and includes not only environmental soundness and economic viability, but social equity as well. In this perspective, issues such as poverty and hunger are as central to achieving agricultural sustainability as those of soil erosion and adequate farm returns.