Submitted to: Agronomy Journal
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/21/2018
Publication Date: 4/12/2018
Citation: Sharratt, B.S., Collins, H.P. 2018. Wind erosion potential influenced by tillage in an irrigated potato-sweet corn rotation in the Columbia Basin. Agronomy Journal. 110:842-849. https://doi:10.2134/agronj2017.12.0681.
Interpretive Summary: Irrigated agricultural lands in the Columbia Basin are highly susceptible to wind erosion, therefore alternatives to conventional tillage practices are needed to reduce wind erosion. We found that wind erosion potential was lower for reduced than conventional tillage practices and most apparent after potato harvest in a potato-corn-corn rotation. Establishing a cover crop after the harvest of potato in autumn considerably reduced wind erosion after potato. Growers in the Columbia Basin can reduce wind erosion and improve air quality for all who live in the region by managing cover crops and tillage after harvest of vegetable crops.
Technical Abstract: Wind erosion is a concern within the Columbia Basin of the Inland Pacific Northwest (PNW) United States due to the sandy texture of soils and small amount of residue retained on the soil surface after harvest of vegetable crops like potato. This study assessed potential wind erosion of an irrigated potato (Solanum tuberosum L. Ranger Russet) - sweet corn (Zea mays L. Triple Super Sweet) - sweet corn rotation subject to conventional and reduced tillage. Sediment flux was measured inside a portable wind tunnel after primary tillage of potato in autumn 2009 and sowing potato and sweet corn in spring 2010. Soil and crop residue characteristics that influence wind erosion were measured concurrently with sediment flux. Analysis of Variance indicated significant differences in soil loss among crop treatments in autumn 2009 and between tillage treatments in spring 2010. Soil loss was greater from potato than first or second year corn in autumn 2009 and from conventional than reduced tillage in spring 2010. Simulations by the Wind Erosion Prediction System (WEPS) indicated that most of the erosion over the three year rotation occurred after harvest of potato in September to the following March. Differences in soil loss among crop treatments or between tillage practices were likely due to differences in residue cover and/or silhouette area. Since wind erosion was most apparent after harvest of potato and from conventional tillage, cover crops should be established soon after harvest and reduced tillage practices adopted to protect the soil from wind erosion in the Columbia Basin.