Submitted to: Journal of Soil and Water Conservation Society
Publication Type: Abstract Only
Publication Acceptance Date: 3/15/1996
Publication Date: N/A
Technical Abstract: Burn/low-till management of winter wheat is being practiced by some growers in the higher rainfall areas of the Pacific Northwest Wheat Region. Detrimental effects on soil quality of burn and till systems are well documented. However, there is little or no data on the effects of burning with no- or low-till annual cropping on either erosion or soil quality. Runoff plots were established in the fall of 1994 on three fields in Columbia county, Washington, and at the Palouse Conservation Field Station (PCFS) in Whitman county, Washington, comparing conventionally tilled and burn/low-till winter wheat after wheat. Field trials of burn/low-till were approved by the NRCS for use in Walla Walla, Whitman, and Columbia counties, and 38 fields were identified by NRCS for this study. In addition to the auxiliary burn sites an additional 18 sites were selected that were not burned to use as comparisons to the burn sites. All auxiliary sites were evaluated in the spring for erosion, residue cover, canopy cover, random roughness, and soil impedance. Little runoff and erosion occurred this season on the experimental plots. However, the runoff and erosion on the plots, though small, was greater on the burned as compared to the conventionally tilled plots for all events but one. The burned fields showed higher microbial activity although the results were highly variable and not statistically different. Twenty four percent of the burned fields experienced soil loss in excess of 5 T/A (single value near bottom of slope, not field average), whereas none of the comparison, no-burn fields, experienced soil loss greater than 5 T/A.