Options to Enhance the Sustainability of Dryland Cereal Cropping in the Northwest
This project, which is nearing completion, focuses on identifying and developing options to enhance the sustainability of dryland farming systems common to six Northwestern states.
Project cooperators have conducted a wide range of research and education activities. Research topics have included soil biology and soil quality, crop rotations, alternative crops and variable landscape management. Educational efforts have included several conferences and workshops, farm tours, on-farm testing, the Sustainable Farming Quarterly newsletter, development of a dryland farming database, and various research and extension bulletins.
In addition to the perennial limitations of the dry climate, major barriers to adoption of sustainable farming systems in the region include the lack of weed control alternatives, financial penalites for sustainable practice implicit in government farm programs and a lack of markets for alternative crops. Erosion control remains the greatest challenge for environmental protection.
Annual Progress Report for 1992
In 1992, several research efforts were completed. Yield mapping technology development at the University of Idaho was further refined during field tests and coupled with variable fertilizer application. With the proliferation of new navigation and sensor technology, precision farming of variable cropland is becoming technologically possible and, soon, will be affordable to growers. This will result in better integration of production inputs (such as fertilizers, herbicides, etc.) and crop management systems (including tillage and rotation) with site-specific landscape conditions. This whole system approach has the potential to reduce overfertilization, pesticide use and soil erosion while improving farm profitability.
Researchers at Pendleton, Oregon, completed several activities funded by the project, and continue to work on other tasks that have resulted from study work. Long-term plots in this study area were used to evaluate the effect of crop rotation and residue management on physiological leaf spot disease of winter wheat. Disease was highest when intermediate levels of nitrogen were present and lowest when no nitrogen was applied. Disease was least pronounced in a wheat/pea rotation; intermediate in wheat-fallow rotation; and severe in continuous annual winter wheat. Results from trials with lupin and lentil indicated optimum seed placement for these crops, but yields were extremely low due to drought.
Soil quality studies of weed plots need Pullman, Washington, were also completed. In several instances, a soil characteristic such as dehydrogenase activity (which indicates a form of microbial activity) was greater in the plots with minimum weed control (and often lower herbicide treatment). This was likely due to the effect of increased weed growth between crop rows where the soil was sampled. The soil in the root areas of the weeds would be expected to support a higher level of microbial activity than a soil devoid of local plant cover. In some cases, the maximum weed control level actually used less pound per acre of herbicide active ingredient than the minimum since more modern low-rate materials were used. This study does not support the hypothesis that current chemically-intensive farming practices in the Palouse region necessarily "kill" the soil.
On-farm testing by growers continues to expand. This activity, initiated by the project and now being promoted by other efforts, is helping growers evaluate newer soil conservation practices, the reduced use of herbicides, improved fertilization approaches and other production issues that can lead to better farm profits and more sound environmental practices.
Information dissemination was accomplished through meetings, newsletters and bulletins. The Sustainable Farming Quarterly, co-produced with AERO, is reaching more than 2,000 readers with every issue; and people mentioned in the articles continue to be contacted for more information. Two publications were released that summarize the historical and current information on dryland cereal/legume cropping systems in the region. Amber Waves is intended for use by growers and agricultural professionals. An overview of the publication is intended for such non-technical audiences as policy-makers, environmentalists and consumers.