|Thorne, Mark - WASHINGTON STATE UNIV.|
Submitted to: Washington State University College of Agriculture and Home Economics
Publication Type: Other
Publication Acceptance Date: February 1, 1998
Publication Date: N/A
Interpretive Summary: With the general upsurge in public interest regarding water, air, and soil quality, producers will have to adopt conservation cropping systems to remain sustainable, profitable, and environmentally sound. More than 60% of the wheat acreage in the state of Washington has a rotation of winter wheat-fallow. This region is characterized by winter annual grass weeds, soil borne diseases, poor soil quality, wind erosion, and severe tillage operations. Generally residue is present on the land only when the winter wheat crop is growing. The "Ralston Project" is the first multi- interdisciplinary study formally organized to examine no-till spring cropping systems in the semiarid and arid regions of the Pacific Northwest. Fourteen scientists from nine disciplines are studying all the cropping systems simultaneously at the same location.
Technical Abstract: The winter wheat/fallow cropping system has become extensively integrated across the inland Northwest landscape. Problems inherent with this system include soil erosion and economic losses from weed, insect, disease concentration, and re-seeding costs when winter wheat plantings fail. The use of alternative cropping systems designed to alleviate these conditions have not been widely accepted or researched. A long-term field study was initiated in 1995 to look at alternatives to the conventional winter wheat cropping system. An integrated, multi-discipline research team was formed to examine weed, insect, disease, economic, crop variety, and soil factors associated with the alternative systems/crops. Crop rotation systems of 1) winter wheat/fallow, 2) spring wheat/fallow, 3) continuous spring wheat, and 4) spring wheat/spring barley were established on a dry-land wheat farm near Ralston, WA. Individual plots are 500 by 30 feet allowing the use of standard farm-size equipment. Duration of the study was to continue throug 2000 allowing each system to complete two full rotations. Following completion of the first two years of the project, all appropriate tillage and rotation systems have been established. Above average precipitation in both crop years produced excellent yields in winter wheat and spring crops. Using no-till technology in growing spring crops has been effective at maintaining a soil cover of crop residue throughout the year that could substantially reduce soil erosion. Weed, insect, and disease factors are being analyzed as each of the first two years have produced varied conditions. Continuation of the study though average and below average rainfall years will help determine economic viability and risk of cropping systems being studied.