Erosion took a serious toll of prime topsoil from wheat fields in the Pacific Northwest United States since farming began in the 1870s. By the mid-1900s, it had become a serious environmental and economic threat to the region that produces world-record rainfed grain yields and almost 13% of the US wheat crop. Of significance is that 80% of the nation's specialty soft white wheat is grown here for food grain, of which 90% is exported. To combat the severe erosion, wheat growers, the experiment stations, and the USDA in Idaho, Oregon, and Washington joined forces in 1975 to develop a multidisciplinary program named Solutions to Environmental and Economic Problems (STEEP). For more than 30 years, it has proved itself a national landmark in effective conservation farming research and education. The basic strategy was a systems approach that addressed all facets of farming from planting to harvesting in multi-year rotations. Its primary goal was to reduce soil erosion from the region's 3.3 × 10 6 ha (8.2 × 10 6 ac), consisting of highly productive but considerably steep cropland. Through the successful development and implementation of improved conservation technology and farming systems by the tri-state STEEP effort, regional soil loss rates averaging 45 Mg ha -1 y -1 (20 tn ac -1 yr -1 ) were reduced over the 30 years to a tolerable 11 Mg ha -1 y -1 (5 tn ac -1 yr -1 ) or less. In addition, financial returns to wheat growers using the conservation systems are equal or have increased, and long-term benefits to soil, water, and air quality have improved. A conservative estimate shows that the investment cost of saving soil and improving water quality was less than $0.50 ha -1 y -1 ($0.20 ac -1 yr -1) over the life of STEEP. Though STEEP can boast success, much more is needed to preserve and protect the Northwest environment, natural resources, and productivity to ensure that agriculture is fully sustainable for the future. Ongoing solutions are needed to resolve emerging issues relating to greenhouse gas emissions, carbon storage, energy costs, and other farm inputs that can affect agricultural health. Its proven success provides strong assurance that STEEP can deal with future challenges relating to changes in farm policy, economics, technology, and sociological issues. This paper documents the extent that program goals were achieved and qualitative estimates of return from money invested.

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In this paper we report on what "sustainable agriculture" means to farmers who seek to develop more sustainable farming systems. Group interviews were conducted with two groups of sustainable farmers in Kansas to learn how they developed their respective approaches, the kinds of parameters they have used to evaluate success and progress, and what other evaluation tools would be helpful to them. For the farmers we interviewed, the central meaning of sustainable agriculture is its holistic approach to assets management. It also means an alternative perspective on what constitutes success in farming. While economic considerations are important, they are balanced by other considerations such as environmental quality, quality of life, and the contributions the farmers can make to their communities. Sustainable agriculture also means an approach to agriculture that entails "thinking risks" as much as financial risks. Lastly, sustainable agriculture means whole farm planning; the farmers we interviewed were more interested in applying whole-farm planning principles based on their local knowledge, than in evaluation tools based on the expert knowledge of researchers and other scientists. The implications of what sustainable agriculture means to these farmers for research and educational programs are discussed.

Abstract:The effects of straw removal from irrigated fields cropped to wheat and barley on soil properties and nutrient cycling are a concern because of its potential impact on the sustainability of agricultural fields. The increasing demand of straw for animal bedding and the potential development of cellulosic ethanol production will likely increase the demand in the future. Previous reviews addressing changes in soil properties when crop residues are removed focused primarily on rain-fed systems. This article reviews published research assessing the effects of wheat and barley straw removal on soil organic carbon (SOC) and analyzes changes in nutrient cycling within irrigated wheat and barley production systems. The effects of straw removal on bulk density, saturated hydraulic conductivity, and other properties are reported from selected studies. Six studies compared SOC changes with time in irrigated systems in which wheat straw was removed or retained. These studies indicated that SOC either increased with time or remained constant when residues were removed. It is possible that bclowground biomass was supplying C to soils at a rate sufficient to maintain or, in some cases, slowly increase SOC with time. A separate research review calculated the minimum aboveground annual carbon inputs needed to maintain SOC levels from nine wheat system studies. Calculations of the minimum aboveground annual C source inputs needed to maintain SOC levels were from rain-fed systems and are some of the best information presently available for use in evaluating residue removal effects in irrigated systems. However, long-term studies are needed to obtain reliable data for diverse irrigated systems. Significant amounts of nutrients are removed from the soil/plant system when straw is removed. Producers will need to determine the cost of the nutrient removal from their systems to determine the value of the straw.Key words: Straw, residue, wheat, barley, small grain, soil organic carbon, nutrients, fertilizer (Soil Sci 2009:174: 303-311) R emoval of straw from grain production fields that have historically incorporated the residues with tillage have many interested parties concerned about the effects on soil properties and nutrient cycling. Several changes and potential changes in straw management have led to these concerns, including removal of straw from grain fields for animal bedding and feed, increased costs of fertilizers and fuel, and the potential development of cellulose-based ethanol production. Because of potential increases in biofuel demand, the ethanol industry will likely be a major cause of more residue removal from cropland. The immediate and long-term effects of removing aboveground crop residues from fields on crop productivity and sustainability are a concern. A series of policies have pushed for the increased production of biofuels, including the