We used linear programming to simulate adoption of manure disposal technologies in eastern Colorado. Manure, either raw or composted, is assumed to be applied to irrigated cropland within 20 miles of feedlots in five subregions of eastern Colorado. We constrained the application so that total N application is no more than the amount used by the crop. N, P and K contents are taken into account, but no benefits are assigned to organic matter or trace minerals and no costs are assigned to soil compaction, weed seed propagation, or inconvenience. Irrigated land within 10 miles of feedlots can easily absorb all manure generated under this scenario. Manure is found to be an economical substitute for chemical fertilizers, assuming N content to be at least 50% that of fresh manure. Composted manure is either more or less profitable than raw manure, depending on its N content. Hauling costs are lower for compost, but composting costs are between $1 and $2 per finished ton. The model does not allow for mixed application of compost and chemical fertilizers, which would increase the value of compost significantly. A feedlot waste sector that composted all feedlot manure in eastern Colorado is predicted to create between 80 and 200 additional jobs.

The long-term effects of cropping practices on plant-available micronutrient concentrations in soils of the northern Great Plains of North America have not been adequately determined. We measured micronutrient uptake by wheat in a crop rotation experiment established at Lethbridge, Alberta in 1911. Phosphorus application at low rates (20 kg P ha-1 yr-1) since 1972 suppressed uptake of Zn, Cu, and Ca in the two years in which they were measured, 1991 and 1993. Vesicular-arbuscular mycorrhizal (VAM) fungi are plant symbiotic fungi that are known to increase the uptake of relatively immobile micronutrients such as Cu, P, and Zn. The functioning of these fungi is known to be affected by high-levels of P fertilization. Assessment of wheat roots showed that low-level P fertilization had significantly reduced the length of root colonized and the percentage of roots colonized by VAM fungi. The results show the importance of considering microbial ecology when assessing the effects of agricultural practices, including low-input practices, on soil productivity and crop nutrient value.

While crop rotations improve soil quality indicators and crop yields in humid temperate regions, much less information is available under harsher arid tropical and subtropical conditions. A field experiment conducted from 1990 to 1993 compared the effect of continuous pearl millet and pearl millet-fallow systems with six rotations of pearl millet that included one, two, or three years of a legume (cluster bean or mung bean). Data were collected on several soil quality indicators and pearl millet yield. Continuous pearl millet monoculture for three y ears did not affect soil organic C, NaHCO3-soluble P, DTPA extractable Fe, Cu, Mn, or Zn, or several soil organic N fractions, but slightly increased activity of dehydrogenase and acid and alkaline phosphatase enzymes. Similar trends were observed for fallow-based cropping systems, except that enzyme activities were lower. Cropping systems containing mung bean or cluster bean improved availability of soil N and other nutrients and increased enzyme activity. These effects increased with number of years of legume. Improvements from cluster bean generally were greater than from mung bean. The lowest pearl milkt yield was obtained with continuous pearl millet and no N, and yields f or fallow-based cropping systems were 13% greater than with continuous pearl millet. Grain yields of pearl millet with two or three years of mung bean in the cropping system were, respectively, 37 and 65% greater than for continuous pearl millet; with cluster bean the corresponding increases were 68 and 101%. Pearl millet yield increased with N applications up to 40 kg/ha under all cropping systems, and up to 60 kg/ha for some cluster bean-based systems. Yield of pearl millet following cluster bean was nearly double that of continuous pearl millet. These results indicate that in hot, dry climates cropping systems that include a legume, especially cluster bean, are more productive, use the limited water supply and fertilizer N more effectively, and improve several soil quality indicators more than do cropping systems without legumes.

The strategic implications of a major, unique effort in the U.S. to expand organic food and agriculture are examined in this article. The authors recently completed an evaluation of the Upper Midwest Organic Marketing Project (UMOMP), funded initially by The Pew Charitable Trusts, and under the guidance of the Midwest Organic Alliance (MOA). The UMOMP was designed to increase the land area under organic production in North Dakota, South Dakota, Minnesota, Iowa, and Wisconsin. On the supply side, the focus was on organic grain, edible bean, and dairy commodities. On the demand side, an increase in organic food consumption was the focus in the Minneapolis—St. Paul metropolitan area. The UMOMP not only encouraged growth in demand, but also aided in the creation of necessary regional organic production, processing, distribution, and retail infrastructure. The UMOMP was generally successful, notably in the increased involvement of mainstream grocery stores in providing and promoting organic food products. Part of this success was due to the MOA's help in forging broker and distributor connections between mainstream stores and regional and national organic suppliers. A broad-based public awareness campaign about organic food and agriculture was another important element in the UMOMP strategy. The organic production and marketing educational effort should help to enable future expansion of organic hectarage. However, serious national or regional strategies to encourage organic farming probably will need other elements as well. Such strategies will involve some fundamental issues about the future structure and nature of organic farming and food systems, e.g., whether organic agriculture can remain centered on small- and moderate-sized family farms that operate in a somewhat independent and entrepreneurial fashion. Whether organic agriculture can be a vehicle for encouraging food systems that are more regional in geographic scope is a related issue. Preserving an organic farming and food system that differs substantially from the presently evolving “industrial” system may necessitate a slower and more deliberate approach than was used in the UMOMP. However, that could involve some sacrifice in the rate of growth in organic supply and demand.

Three hypersensitive resistant, six partially resistant (slow rusting), and one susceptible spring bread wheat (Triticum aestivum L.) cultivars were evaluated for grain yield, test weight, and kernel weight under artificially created epiphytotics of leaf rust disease (caused by Puccinia recondita f. sp. tritici) with and without fungicide protection for three years. Rusted plot yields were 4 percent lower compared to fungicide-protected plot yields for cultivars with hypersensitive resistance. In rusted plots, grain yield and kernel weight averaged 8 percent less for cultivars with partial resistance but varied from 2 to 20 percent less depending on cultivar. The susceptible check cultivar, Yecora 70, averaged 27 percent lower grain yield, 22 percent lower kernel weight, and 6 percent lower test weight in rusted plots. Slight reduction in test weight was also observed for each cultivar. Losses in grain yield could, therefore, be reduced to levels similar to those of hypersensitive resistant cultivars by the use of partial resistance. We discuss the sustainability of partial genetic resistance to leaf rust. Since partial resistance is expected to be durable, and since rust levels and effects on yield in farmers' fields are likely to be less than in this experimental plot study, partial resistance should give long-lasting resistance at a negligible cost in yield that is insufficient to justify the use of fungicides.

Agricultural soil quality (SQ) research has focused on the influence of individual soil properties, particularly those related to soil organic matter (SOM), on soil processes such as water movement and retention, and nutrient cycling. However, few studies have assessed the influence of these SOM-related properties on crop productivity, particularly under different management systems. Furthermore, agricultural SQ research in tropical regions is limited. The objectives of this study were, for a tropical site, to determine (1) the relationship between selected soil characteristics and resulting soil functional properties such as aggregate stability and porosity, and (2) the relationship between SQ indicators and productivity of corn under three different tillage systems. Twelve plots were randomly demarcated in three adjacent fields under different tillage systems. Profiles were described by augering and the surface soil (0–7.5 cm) was sampled just prior to crop harvest and analyzed for texture, standard soil tests (pH, available P, K, Mg and Ca) and SQ parameters including total N, total and active fraction C, porosity and aggregate stability. Corn dry grain m−2, above-ground crop dry matter m−2, and dry grain per plant was measured in each plot. Soil C parameters were highly predictive of macroaggregate stability and soil porosity across different tillage systems. Macroaggregate stability and soil C (particularly active C oxidizable by 0.025m KMnO4) were highly correlated with crop productivity across tillage systems. These findings suggest that soil C in the surface layer, especially the active C fraction, markedly affected the productivity of this tropical soil through its influence on soil structure.

With the passage of the 1990 Clean Air Act came the responsibility to monitor and control particulates in the size range 10 μ and smaller (PM10). Many urban areas, particularly in the western U.S., have experienced concentrations of fugitive dust particulates from upwind sources that exceed the federal health standards. Often a significant amount of this material is generated upwind on agricultural fields, and then is entrained and transported in the regional air mass, thus degrading the air quality in downwind urban regions. Current technology cannot adequately quantify the fugitive dust emitted and transported from agricultural sources, nor specify adequate control methods. A comprehensive research plan recently was developed and initia ted for the Columbia Plateau of eastern Washington State that involves multiple disciplines and several state and federal agencies. This research has several components: characterizing the soil, vegetation and climate in a region of 136,000 km2; developing wind erosion and fugitive dust emission relationships for individual farm fields; developing and applying transport-dispersion-deposition models of the region; selecting and testing farm-level control strategies; and providing public information to both the urban and farm communities for understanding the problem and developing management plans. Simultaneous receptor analyses and public health research combine to make this a comprehensive regional research effort on fugitive dust emissions and impacts.

Little is known of how vertebrate pest and beneficial species respond to cover crops in vineyards and orchards. During spring 19941 interviewed 22 people who work with cover crops in California and searched for vertebrates and their signs in 36 field plots where cover crops were grown. Farmers usually relaxed concern for vertebrate pests after planting cover crops. But cover crops were thought to increase venebrate damage to trees and vines when planted continuously across the rows or grown in orchards and vineyards less than three years old. Vertebrates usually were not abundant or harmful to the commercial crops and cover crops I examined. Gophers were most abundant in older, uneven, scrappy, or weedy cover crops. They preferred beneficial and insectary blends and Cahaba white vetch, and were least abundant in grasses, subclover mixes, and bur medic. Voles preferred nontillage clover mixes, but avoided bare ground under vine and tree rows. All small mammals were more numerous near streams and recently tilled fields. Cover crops attracted many predatory vertebrates, which improve the aesthetic quality of the farm and might keep animal damage to economically acceptable levels. Cover crops can contribute to wildlife conservation in California, especially if the area in cover crops continues to increase.

This paper examines whether the dollar value of health benefits that consumers derive from organic food could account for the price premiums they pay. Price and sales data from realized transactions are inadequate to reveal consumer preferences for health benefits. Our exploratory alternative method estimates the value of health benefits to a hypothetical consumer who assesses risks as risk assessors do and values a unit reduction in all fatal risks equally, regardless of the source of any risk. Under these assumptions, our estimates of the value of health benefits derived from substituting an organic diet for a conventionally produced diet approach zero. For a common organic product, apple juice, we estimated the cost of reducing risks by buying the organic characteristic. The cost of averting each adverse health outcome is 27 to 461 times as large as the value of benefits. If the characteristics of our hypothetical consumer match those of the typical consumer, two inferences follow from our estimates of benefits and costs. First, the typical consumer is unlikely to purchase organic food for health reasons. Second, consumers who choose organic food could differ from typical consumers in several dimensions: perceptions of the level of risk from dietary intake of pesticides, perceptions of the nature of adverse health outcomes from pesticides, or in the importance attached to other attributes of organic food. Our analysis is exploratory partially because there are several behavioral assumptions implicit in the values we calculate. Also, we focus on risks that can be quantitatively estimated, measuring the probability of an adverse health outcome with readily accessible data. Currently, only cancer risks can be measured in terms of probabilities from readily accessible data.

United States farm policy has a long tradition of subsidizing farmers in order to achieve national goals. The issue of agricultural subsidies poses a particular challenge in terms of relevant policy design. This paper explores the potential for economic indicators to guide policies that encourage sustainable agriculture through alternative-oriented approaches. We begin by reviewing several indicators of sustainable agriculture that have been proposed previously. We then suggest a set of three economic indicators: energy and machinery use, creation of local jobs, and feed balance, and apply them to two groups of farmers: conventional farmers and those with an explicit orientation towards sustainable agriculture. Though our survey groups cannot be compared statistically, it appears that these three indicators are capable of distinguishing between the two farmer groups. We conclude with some suggestions for further research and application.

Researchers at land-grant universities are under pressure to widen their research objectives, which requires them to expand their inquiry from a disciplinary base to a systems level, to include farmers and nonuniversity organizations as research collaborators, and to communicate with broader sectors of the public, such as consumers and policy makers. However, there are few rewards for scientists who undertake long-term, systems based research. An approach that brings together multidisciplinary, multiprofession teams using a radial model of organization has successfully addressed these challenges in Wisconsin. A small “hub” manages the team, with the remaining participants linked to component taskforces or “satellite” projects. This enables research to be done on both multidisciplinary and related single-discipline questions. Radially organized teams can attract diverse people with different time commitments and reward incentives. The research meets the criteria of public and academic audiences alike. For innovative research and extension efforts like radial teams to reach their full potential, larger institutional changes are needed within the land-grant system and professional agricultural societies.

We coupled a nonlinear mathematical programming model with sensitivity analysis and evaluated some economic barriers to adoption of low-input agriculture by farmers in Richmond County, Virginia. Collection of primary data made the model more realistic. We analyzed potential barriers to adoption, including poultry litter price, yields, labor requirements, and variable input costs. We found the adoption of low-input practices to be sensitive to the price of poultry litter and relatively insensitive to yields, labor requirements, and variable costs. However, when several of these barriers are combined, the model predicts that farmers would use conventional practices. Therefore analysis of the farm as a system rather than practice by practice is important when identifying the effects of economic barriers.

Those engaged in agriculture possess a definite but unexamined moral confidence or certainty about the correctness of what they do. This paper examines the origins of that confidence and questions its continued validity. The paper argues that those engaged in agriculture are morally confident about the rightness of their activity. The basis of the moral confidence is not obvious to those who possess it or to the public. In fact, the moral confidence that pervades agricultural practice is potentially harmful because it is unexamined. Suggestions for expanding agriculture's moral scope are made to approach the question of where moral values originate, and what are, or ought to be, the moral standards for agriculture in our post-industrial, information-age society. Part of expanding agriculture's moral scope will be giving up some of our hubris about the goodness of our culture and its agriculture. The paper advocates analysis of what it is about our agriculture and our society that thwarts or limits our aspirations for agriculture and needs modification. We must strive to nourish and strengthen those features of our agriculture that are beneficial and change those that are not. To fit ourselves to this task, we must be sufficiently confident to study ourselves and our institutions and dedicated to the task of modifying both.

The soil erodibility factor (K) of the Revised Universal Soil Loss Equation is currently considered a constant for all soils in the same type, regardless of production practice. To examine the effect of alternative production systems on the K-factor we compared pairs of alternatively and conventionally farmed fields on a Judson silt loam (Fine-silty, mixed, mesic Cumulic Hapludolls), a Yutan silty clay loam (Fine-silty, mixed, mesic Mollic Hapludalf), and a Wann fine sandy loam (Coarse-loamy, mixed, mesic Fluvaquentic Haplustolls). Soil cores were taken from the surface 10 cm and analyzed for organic matter, permeability, structure, and texture. These data were used to estimate K-factors from a nomograph. All soils in the study had a fine granular structure. Organic matter content and permeability were significantly higher for the alternatively managed field at every location, except for no difference in permeability on the Judson soil. However, the K-factor was significantly lower for the alternative system on the Judson soil. Of all the parameters, texture has the greatest influence in determining K-factors within the nomograph, with soils higher in silt being more erodible than soils higher in sand or clay. Thus, the influences of alternative production systems affected the Judson soil to a greater degree than other textures because of its higher inherent susceptibility to erosion. This study shows that alternative production systems affect the K-factor of some soil types and can reduce soil erodibility, and therefore should be considered when developing conservation plans.

Participatory assistance (PA) is a proposed approach for promoting change that involves both the biophysical processes of farms and the management processes of farmers. It integrates external expertise, inputs, and expectations with the unique character of a particular farming system. It focuses on improving the processes of the farm and farmer rather than on the traditional interests of “outsiders” such as disciplinary researchers, industry sales people, government regulators, consumers, or environmental interest groups. As an alternative to transfer of technology, it promotes learning both by the farmer and by specialists from academia, industry, government, and the public. Participatory assistance can promote innovations in the operation of farms, in the conduct of research and education, in the development of products and services, in the formulation of policy, and in the involvement of the public in agriculture. The outcome is not assumed to be the adoption of the “best” technology, but may be found in the emerging properties that result from innovations. Assessing the improvement that follows each innovation will require clear specification of the relevant performance criteria, provision of appropriate technical support, and reinforcement by the appropriate incentives. Reconciling today's farming with water quality protection illustrates the potential of the PA approach.

In the United States, trees constitute an element in agriculture whose importance has been inadequately appreciated. In actuality, they are highly important in several ways. From the time of the earliest settlements, they have served as a source of building materials and energy. They protect the soil against erosion by wind and water. When used as windbreaks adjacent to crop fields, they protect crops against the damaging effects of wind on crop yields. As windbreaks for livestock, they increase feed conversion efficiency, improve weight gains, and increase the survival rate ofnewborns. They provide habitat for wildlife and contribute aesthetically to the appearance of the countryside. They protect water resources. Trees need to have the story of their great benefits more widely and emphatically told.

Modern, conventional agriculture has generalized the technology of farming, minimizing the significance of the relationship between farmers and their particular land. This generalization undermines farm culture and impedes its transmission from generation to generation. To avoid making the same mistake, ecologists designing the new, lower input agriculture should: 1) reject any black box presentations of their systems that the farmer cannot understand and that interfere with the relationship between the farmer and the land; 2) make systematic efforts to rediscover traditional farm wisdom and incorporate it into the new system; 3) utilize academics in a major program of local, adult education for farmers; and 4) reorganize extension services to facilitate the lateral transfer of information from farmer to farmer, and develop methods of incorporating farmers into the agricultural research process at the planning stage.

In 1993, a breakthrough occurred for sales of organic food products in conventional supermarkets in Denmark. Since then, sales have increased markedly and consumers now have a choice between organic and conventional food products in nearly all supermarkets. This success owes much to the intense efforts of three main groups since the mid-1980s. First, organic farmers have increased production and successfully managed economic and organizational problems. Second, the Danish State has supported sales of organic products and farmers' conversion to organic farming by supporting marketing and product innovation and by organizing producers. Third, the largest Danish supermarket chain has contributed by its steady demand for organic products since 1981. Today, all major supermarkets in Denmark are supplied by conventional distributors that handle the products of small organic producer organizations. For nearly two years the system has kept up the positive effects of a market expansion process that was initiated by a major advertising campaign and a modest drop in consumer prices.

One widely held view of the future of American agriculture is that it will continue the current trend toward fewer but larger farms, greater centralization and vertical integration, and declining rural populations. If so, the research, teaching and extension institutions created to serve agriculture will not survive unless they can adapt to changing political and demographic conditions, especially the domination of the suburbs. This will require these institutions to set new goals for themselves. Their historic pursuit of increased technical efficiency already has been so successful that it has sharply reduced the farm population, which has been their main base of public support. Suburban America, in contrast, will demand an agriculture that is more in harmony with nature. Alternative notions of the Common Good can provide the philosophical basis for this shift Historically, the economic system, including agriculture, has regarded nature as something to be used to advance human well-being. In this view (which could be called “Liberal” in the 19th century sense of the term), the reason to protect nature is to insure that it can continue to serve human needs. In contrast, the “Ecocentric” view of the Common Good emphasizes that humans are part of an ecological community, and that we must optimize the balance between human needs and the health of the ecosystem.

The market value for organically grown produce in California was estimated to be at least 54 to 68 million dollars at wholesale prices in 1987. This market is rapidly growing. A 41 percent increase in the value of organically grown produce was observed in 1987. When this analysis was completed in early 1988, it was estimated that the wholesale value of the market could exceed $300 million by 1992. A sample analysis of 1986–1987 price and volume for organically grown broccoli showed relatively steady prices and a volume increase of over 50 percent, indicating a similar growth in market demand. Prices for organically grown produce are significantly higher than for conventional produce; however, in spite of high weekly volume volatility, organic prices appear to be less volatile than prices for conventional produce. This paper proposes that the collection, reporting, and analysis of organic produce market data be continued and improved and that new sources of data be integrated to ensure continued availability of timely market information. Availability of more market information should increase efficiency and aid the development of the organic produce industry. The paper also proposes that overall trends in the organic produce industry be systematically monitored by Federal-State Market News and that the increased use of market information by organic growers, growers considering the transition, and other interested parties in the industry be promoted.