We evaluated free-range domestic chickens and geese as components of a nonchemical apple orchard intercropped with potato. Chickens and geese were compatible with the system but provided different benefits and had different requirements. Chickens were omnivorous and highly active throughout the day, and dispersed throughout the available area. In contrast, geese were strictly herbivorous and less active, and usually remained close to their coop and water source. Geese substantially reduced vegetation biomass under the trees and around the potatoes without damaging either crop. Chickens reduced noncrop vegetation biomass slightly but also consumed several insect species, including Japanese beetle and Colorado potato beetle. Factors influencing the feasibility of integrating domestic chickens or geese into agroecosystems are discussed.

Within the past decade, low cost and convenient soil tests have been developed and marketed to permit better matching of soil nitrogen levels with crop needs. We explore the factors related to farmers' initial adoption and their commitment to continued use of one such kit, marketed in Iowa as N-Trak. Early adopters of the N-Trak had many of the same personal and farm operation characteristics as farmers who have been early adopters of other farming innovations. Further, the principal factors in differentiating between various levels of commitment to continued use of the kit were perceptions of technological attributes of the kit and, to a much lesser extent, farmer attitudinal factors and personal characteristics. These results suggest that perceived attributes of the technology, especially its returns to time, effort, and financial investment, were critical in the decision to adopt and continue to use the N-Trak kit. Early adopters' decisions to continue using it focused primarily on cost, profitability, and technological issues, to the exclusion of water quality concerns measured by attitudinal items. These findings suggest that providing information that shows the kit's ease, compatibility, and advantages, would be more persuasive than marketing it as a tool to enhance water quality.

The publicly sponsored agricultural research system in the United States has always had to deal with the tension between public expectations and scientific practices and standards. The equilibrium it established between those two contradictory demands has been unraveling since the 1960s. The contemporary challenge to the system is to redefine its public and scientific roles in an environment of rapid scientific change and of public debate and disunity.

Biological control of arthropod pests has a long history of useful practical application. Parasites, predators, and pathogens have been employed in many cases to control pest arthropods in an efficient, cost-effective, and permanent manner. The traditional tactics used in biological control (classical, augmentation, and conservation) remain vital and valuable tools in the biological control of pests for agricultural crops, range lands, forests, and glasshouses. New technologies offer promise. One emerging technique involves the genetic improvement of natural enemies of arthropods through selection, hybridization, or recombinant DNA technology.

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.

This paper discusses data on plant-nutrient conservation in Sweden between 1950 and 1980 and on plant-nutrient balances in conventional and alternative farming. The amounts of plant nutrients supplied in the form of artificial fertilizer in Sweden increased severalfold between 1950 and 1980. The amounts of N and P applied were four times higher than those recovered in agricultural products. This difference not only represents a loss to farmers but also a burden on the environment. This problem is a consequence of the increased separation of crop management from animal husbandry in Sweden. The flow of plant nutrients through the agroecosystem can be represented as follows: Artificial Fertilizers- > Crop Production-> Animal Husbandry- > Losses (air, water, or immobilization).

This paper suggests that all farms in Sweden can operate effectively without relying on applications of highly soluble plant nutrients. By recirculating plant nutrients in manure and cultivating nitrogen-fixing species, the need for artificial fertilizers can be eliminated while minimizing nutrient losses and their associated adverse effects on the environment. Successful alternative farms provide practical examples of how a farming system can eliminate its dependence on applications of highly soluble plant nutrients by stressing effective nutrient economy and biological activity. The strategies they use include: matching animal management practices to the farm's own production of feed, thereby reducing net removal of plant nutrients per unit area (in Sweden 0.6–0.8 animal units per ha); minimizing nutrient losses through careful manure management and by using cover crops; and supplying N by nitrogen-fixing ley species, and P and K by soil weathering and by applying supplementary soil improvement materials.

Synthetic inputs have become the norm in cash grain production in the Midwest U.S., but do they really increase profitability compared with low-input production methods? This study reports a comparison of cash grain yields, quality and profitability under two management systems, low-input practices and conventional practices. The crop sequence was corn, soybean, and wheat - medium red clover green manure. Low-input practices included crop rotation, manure, and mechanical weed control. Conventional practices added starter fertilizer, side-dress N for corn, early spring topdress N for wheat and herbicides to the low-input practices. The conventional inputs increased yields in each of the five growing seasons, 1992–96. Weather, N fertilizer and weed control appeared to explain much of the yield and grain quality variation. Soil P and K levels were maintained or increased by manure use. Plant foliar analysis indicated that soil macronutrients were mostly in the sufficient range for both management systems. Economic return in excess of the additional cost of the fertilizer and herbicides averaged $172.63 ha−1 for soybean, $165.63 ha−1 for corn and minus $19.19 ha−1 for wheat over the five-year study. Fertilizer and herbicides did pay with corn and soybean, but not with wheat under the conditions of this study.

The Wisconsin Integrated Cropping Systems Trial has been comparing different farming systems on two farm sites in southern Wisconsin since 1989. Inexplicable differences in the yields of corn grown in three systems stimulated research on the relationship between yield and the dynamics of root growth. The three systems were continuous corn with mineral fertilizer (CS1), corn—soybean—winter wheat—red clover (CS3), and corn—oat + alfalfa—alfalfa with dairy manure applied (CS5). Four or five sequential root samplings were taken each growing season on two sites for 3 years. Soil monoliths were taken from around the base of the plant and washed out over a 1-mm sieve. Estimates were obtained of the length and health of roots from different nodes that were attached to the crown of the plant. The seasonal accumulation of root length was estimated by summing the maximal root length produced at each root node. Corn grown in monoculture averaged 7.5 Mg of grain/ha, which was similar to corn grown after red clover green manure (7.3 Mg/ha) but less than corn grown after alfalfa with manure (8.5 Mg/ha). Contrary to expectations, corn grown in monoculture averaged 26% more root length over the season than CS3 and 12% more length than CS5. The differences were mostly due to increased production of later sets of roots (nodes 6–9) for the corn in monoculture. However, for the first sets of nodes (seminal—node 5) the percentage of healthy roots was lower in the monoculture system (59%) than in CS3 (63%) or CS5 (76%). The increased root growth associated with corn grown in monoculture may be a response to poor root health. Regressions with root growth accounted for a large amount of the variation in grain yields. Corn grown after alfalfa with manure achieved higher yields with less roots than did corn grown in monoculture. Yields in the former system plateaued at root lengths of 1 cm/cm3 and greater, producing grain yields that ranged from 8 to 10 Mg/ha. Corn grown in CS1 and CS3 showed curvilinear responses with calculated yield maxima of 8.7 and 9.9 Mg/ha at root lengths of 2.12 and 1.74 cm/cm3, respectively. Intensifying the use of rotations and organic manures seemed to increase the ability of the corn rooting system to support grain yields. The cause for this greater efficiency is not yet clear, though root health may be an important factor.

Two conventional cropping systems (winter wheat/dry peas and winter wheat/spring barley/dry peas) in the dryland grain region of southeastern Washington were compared with several alternative systems regarding profitability and environmental impacts. Two of the alternative systems use green manure crops and have low fertilizer and pesticide requirements. The remaining two are otherwise conventional rotations modified to include soil-building crops, bluegrass seed and rapeseed.

Estimates of annual off-site erosion damage ranged from $6.56 to $20.50 per rotational acre, while on-site damage estimates ranged from $0.50 to $1.55 per rotational acre. Estimated leaching losses of pesticides to a water table 3.6 feet deep were negligible, but significant leaching losses of nitrate-N were predicted to occur from fall-applied inorganic fertilizer.

Including bluegrass in a conventional grain rotation increased estimated net returns over variable costs by 16% and decreased soil loss by 33% compared with the most profitable conventional rotation. The next most profitable alternative system, rapeseed plus a conventional grain rotation, had slightly higher net returns over variable costs than the second most profitable conventional rotation, with slightly less soil loss. When fixed costs of machinery depreciation and land are included, the alternative systems fared relatively better. An experimental wheat/pea/medic system had higher projected net returns over total costs than the most profitable conventional rotation, while averaging just one-third as much soil loss per year. A wheat/barley/sweetclover green manure rotation was similar in profitability to the less profitable conventional rotation, but had only two-thirds as much soil loss.

We constructed a mixed-integer linear programming model to determine the profitmaximizing combination of conventional and alternative rotations under 1990 farm bill provisions. Planting all or nearly all land to the bluegrass plus conventional grain rotation maximized returns over total costs for high, medium, and low program crop price scenarios. Farmers maximized profit by participating in both the wheat and barley programs under the low price scenario, only in the wheat program with moderate prices, and in neither the wheat nor the barley program under the high price scenario.

Anecic earthworms (e.g., nightcrawlers) create deep, vertical burrows and feed by dragging organic matter from the soil surface into the burrow, thereby incorporating organic matter. The incorporation of leaf litter in orchards may reduce inoculum levels of organisms that cause diseases such as apple scab. However, anecic earthworms are generally absent from agro-ecosystems in California, in part possibly because of low rainfall and seasonal drought. Anecic earthworms (Lumbricus terrestris) were introduced to an organic apple orchard in Watsonville, California, where the resident earthworm community included only the endogeic (subsurface-feeding) species Aporrectodea caliginosa and Microscolex dubius. With L. terrestris present, incorporation of apple leaf litter increased from less than 28% to 79%. Yearly patterns of activity of resident earthworm species were unimodal, corresponding to the winter season of peak rainfall and low soil temperature. Earthworm populations were similar for organic and conventional treatments until the third year, when abundance and biomass of resident species were significantly greater in the organic plots.

For four years (1991–1994), gestating gilts rotationally grazing alfalfa were compared to gilts in a dry lot fed 1,800 g/d of a corn-soy diet (control). The dietary supplementation treatments for the grazing gilts were 1,260 g, 720 g, and 180 g of ground corn (70, 40, and 10% of the gilts' energy needs) plus 45 g of monosodium phosphate and 9 g of salt (sodium chloride) per day. All gilts were fed individually. In 1991 and 1992, the gilts were fed daily. In 1993 and 1994, the gilts were fed their weekly feed ration in three equal feedings on Monday, Wednesday, and Friday. Alfalfa paddocks were grazed for one week with a stocking rate of 62 gilts/ha/wk. All gilts had rings in their noses to minimize rooting. For the 42-d mid-gestation trial, the weight gain of the control gilts did not differ from the gain of the grazing gilts daily fed 720 g corn (40%) (P<.05). The interval feeding reduced gains compared to the daily feeding. Gilts daily fed 1,260 g corn/d (70%) gained more than the other grazing treatments (P<.05). The gilts daily fed 180 g corn/d (10%) gained less than all other treatments (P<.05) and had the greatest backfat loss (P<.05) for the 42-d trial. No major trends were noted in number of pigs born per litter or pig birth weight. After one week of grazing, alfalfa height decreased 14.7 cm and DM content of the remaining alfalfa increased 9%. Each grazing season, the alfalfa stand decreased 3.8 plants/m2. Daily alfalfa intakes per gilt were calculated at 11.5 kg (3.2 kg DM) for 1991 and 1992, and increased to 16.3 kg (4.2 kg DM) for 1993 and 1994. These are composite intakes because all grazing gilts were commingled. Mid-gestation gilts rotationally grazing alfalfa need 720 g of corn per day plus phosphorus and salt to match weight gains of gestating gilts in a drylot fed 1,800 g/d of a corn-soy diet. Daily feeding, rather than interval feeding, resulted in greater weight gains and lower alfalfa intakes. The practice of grazing gestating sows has the advantages of no manure to haul, reduced purchased feed inputs, and inclusion of a soil-building crop like alfalfa in the crop rotation.

Agricultural landscapes are essential for preserving biodiversity, even though agricultural activities are the leading cause of habitat degradation worldwide. About half of the Earth's productive land area is farmed or grazed, whereas only about 6% of the total land area is protected for native species and ecosystems. The ecological services of healthy ecosystems are fundamental to agriculture, and these services depend upon a large number of species interacting with each other and with inorganic nutrient cycles. Likewise, the quality of ecosystems between reserves is critical to the persistence of species and ecological processes within reserves. Thus, conservation-oriented farming methods are critically important for both agriculture and biodiversity. Three examples illustrate agricultural practices that benefit the farmers, the local ecosystem and the landscape: (1) In Minnesota, rotational grazing, evaluated by the collaborative research of farmers and scientists, improved soil, pasture and stream quality, and boosted the confidence of the farmers in developing more sustainable grazing practices. (2) Predator-friendly ranching in Montana, in which nonlethal methods are used to protect livestock from depredation by native predators, benefited the ranchers with premium prices for wool and meat. The persistence of native predators, many of which have been on endangered species lists for years, benefited the regional ecosystem. (3) Shade-grown coffee in Latin America, in which coffee shrubs grow under an intact forest canopy, often looks and behaves ecologically like native forest and may house high levels of native biodiversity. This system benefited farmers, as long as they received a price premium for shade-grown coffee. The economic viability of these conservation-oriented practices depends upon farmers receiving price premiums for their products and by society rewarding fanners for their practices. A vision of ecological farming as the dominant form of agriculture is presented, with benefits at the scale of the farm, the landscape and society.

What scientists include among the essential attributes of sustainable agricultural systems can influence the development of agricultural research agendas and how research is done. Current perspectives on sustainability place varying emphasis on environmental and agrarian values and propose different amounts and kinds of change in agricultural production, agricultural science, and rural social institutions. In a delphi study, agricultural scientists at North Central region land-grant universities considered environmental management and development of new farming technologies as essential to a definition of sustainable agriculture, but gave little importance to social or scientific restructuring. With some qualifications, we characterize their view of sustainability as a stewardship perspective that does not include social considerations and explicitly rejects radical social change.

Wildlife and fish have much to gain from the movement toward alternative, sustainable agricultural practices. Interrelated reasons for the habitat improvements to be expected from a change to sustainable systems include reduced use of agricultural chemicals, better care of the soil, and reintroduction of greater landscape diversity. The most well-documented benefits would result from reduced use of agrichemicals, which often are toxic and frequently change the structure and composition of available food and cover. The wildlife benefits of erosion prevention and landscape diversification are less well-documented but may be as significant for habitat improvement. The opportunities to enhance habitat using sustainable farming methods are beginning to receive increased attention from wildlife professionals. As a result, efforts are under way to expand use of sustainable methods on farmlands managed by the U.S. Fish and Wildlife Service.

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.

I interviewed 19 county agricultural extension agents about their views of alternative agriculture as it is being promoted by sustainable agriculture groups in Minnesota. They varied considerably in how much they knew about it, their openness to it, and how heavily they were involved in it County extension agents share broad economic and environmental goals with sustainable farming advocacy groups, but many believe that agriculture is already working to meet those goals and are skeptical of the feasibility of alternative agriculture. Extension agents generally did not accept as realistic a primary social goal of sustainable agriculture advocates: maintaining the number of family farms. If county extension agents and sustainable agriculture groups in Minnesota are to work together for more sustainable agriculture, open discussion is needed on the goals of agriculture and visions for its future.

The Pacific Northwest dryland region is moving toward conservation tillage to control excessive erosion on steep slopes, but progress has been slow because of adverse effects on plant growth and yield. Fertility relations in cereal grains with conventional tillage are well known, with deficiencies occurring for nitrogen, sulfur, and phosphorus, in declining order of frequency. N and S deficiencies are more severe in conservation tillage, although the pattern of crop response to nutrient application is the same as in conventional tillage. Placing nutrients in a subs urface band near the seed is more effective than broadcasting on the surface. Higher fertility is required near developing root systems to offset greater competition from grassy weeds and more intense pressure from root-pruning soil pathogens. Conservation tillage alters soil fertility and plant growth in different ways on different landscapes. These differences must be considered to ensure tha t conservation tillage will be effective over the entire field.

We evaluated selected cool-season annual and perennial legumes as potential ground covers to supply nitrogen and to increase beneficial arthropod populations in a pecan orchard. Densities of aphids (Homoptera: Aphididae), lady beetles (Coleoptera: Coccinellidae), damsel bug (Hemiptera: Nabidae), green lacewings (Neuroptera: Chrysopidae), brown lacewings (Neuroptera: Hemerobiidae), hover flies (Diptera: Syrphidae), spined soldier bug and other stink bugs (Hemiptera: Pentatomidae), and spiders (Araneida) were monitored at 7–14 day intervals during the growing season for three years. Aboveground biomass production and nitrogen content of the legumes was measured for two years. Aphids peaked during early spring each year, with the highest density usually on ‘Dixie’ crimson clover and ‘Kenland’ red clover. Density of lady beetles was positively correlated with that of aphids, but spider densities were not. Other arthropods usually were not abundant. Nitrogen in the tops of the annual legumes ranged from 20 kg/ha to 89 kg/ha when assessed after a single harvest at anthesis; for the perennial legumes it was from 108 kg/ha to 179 kg/ha following two harvests in June and September. We chose two annual legumes (‘Dixie’ crimson clover and hairy vetch) and two perennial legumes (‘Louisiana S-1’ white clover and ‘Kenland’ red clover) for further evaluation.