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ARS Home » Pacific West Area » Pendleton, Oregon » Columbia Plateau Conservation Research Center » Research » Publications at this Location » Publication #82577

Title: EROSION AND CROP RESPONSE TO CONTOUR-RIPPED PLANTED-WHEAT IN SEASONALLY FROZEN SOIL OF THE PACIFIC NORTHWEST

Author
item Williams, John
item Wilkins, Dale
item SCHILLINGER, WILLIAM - WASHINGTON STATE UNIV

Submitted to: Seasonally Frozen Soils Symposium
Publication Type: Proceedings
Publication Acceptance Date: 1/8/1997
Publication Date: N/A
Citation: N/A

Interpretive Summary: Grooves can be ripped in soil containing recently planted wheat. This technique, in which the grooves are ripped following contour lines, provides protection against erosion in seasonally frozen soil. In this paper and accompanying poster, we discuss preliminary findings and present an overview of this conservation technique. In the Pacific Northwest our worst erosion occurs during winter months with light, slow rainfall falling on thawing soil. Long, steep slopes and minimal plant cover are characteristics of landscapes most impacted by this type of erosion. Winter wheat-summer fallow cropping practices, the most common farming practice in this region, makes these conditions worse. We put together information that discusses contour ripping frozen soil planted to winter wheat in the Pacific Northwest. This information shows that slope length is effectively shortened and runoff decreased when this technique is used. The channels keep water on the slope, reduce runoff and erosion, and allow the water to percolate into the soil. This process increases the amount of water stored in the soil profile for later crop use. Contour tillage can be done without significant damage to crop yield or an increase in disease. However, effectiveness decreases rapidly with each storm following contour trenching. The technique is best used on slopes with deep soil for water storage and, also, slope where erosion is known to be a problem.

Technical Abstract: We prepared this paper to accompany a poster presentation contour- ripped planted wheat in seasonally frozen soil. The purpose of the paper/poster was to present preliminary findings and an overview of this conservation technique. Soil erosion in the dryland farming region of the Pacific Northwest is most prevalent in winter months with low intensity rainfall falling on thawing soil. Long, steep slopes and minimal green or residue cover are characteristics of landscapes most impacted by this type of erosion. Winter wheat-summer fallow cropping practices exacerbate these conditions by creating nearly fully (water) recharged soil profiles. We reviewed literature that discusses contour ripping frozen soil planted to winter wheat in the Pacific Northwest. This practice breaks slope length by opening channels through the frozen soil and plow pan. The channels detain water on the slope, reducing runoff and erosion, and allow infiltration, thus increasing water stored in the soil profile. Contour tillage can be done without significant damage to crop yield or pathogen infestation. However, the conservation effectiveness decreases rapidly with each storm following contour trenching; and conditions of steep slopes or shallow soil however, caution must be used with the prescription and application of this conservation treatment. Erosion and Crop Response to Contour- Ripped Planted-Wheat in Seasonally Frozen Soil of the Pacific Northwest.