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Soil Management Strategies for Sustainable Corn Stover Harvest.

Poster Number 2803

Monday, November 4, 2013
Tampa Convention Center, East Hall, Third Floor

Douglas L. Karlen1, Stuart J. Birrell2 and John L. Kovar1, (1)USDA-ARS National Laboratory for Agriculture and the Environment, Ames, IA
(2)Agriculture & Biosystems Engineering, Iowa State University, Ames, IA
Corn (Zea mays L.) stover has been identified as a primary feedstock for cellulosic bioenergy production in the U.S. Midwest because of the vast area upon which the crop is grown. We conducted five years (2008 – 2012) of field research designed to quantify short- and long-term effects of stover harvest on Mollisols in central Iowa, U.S.A. Chisel plow and no-tillage practices were used to produce corn using standard, 75 cm row spacing and a population of 7.9 plants m2 or in twin-row configuration with a population of 9.4 plants m2. A single-pass combine was used to harvest grain and an average of 0, 3.9, or 6.0 Mg ha-1 yr-1 [LSD(0.1) = 0.3] of stover from single-row or 0, 4.5, or 6.1 Mg ha-1 yr-1 [LSD(0.1) = 0.3] of stover from twin-row treatments each year. SamplePoint software was used to estimate surface cover following the 2011 and 2012 harvest seasons. Average post-harvest cover for the three stover treatments was 94, 84, and 70% [LSD(0.1) = 4.4] for single-row and 97, 86, and 77% [LSD(0.1) = 3.4] for twin-row configurations. Photos before and after chisel plowing in 2012 showed that tillage decreased average residue cover to 27 and 33% for single- and twin-row treatments, respectively. Grain yields showed significant seasonal differences primarily due to rainfall amount and distribution, with the highest levels for both planting configurations being 12.5 Mg ha-1 in 2010 and lowest being 8.5 and 8.7 Mg ha-1 for single- and twin-row configurations in 2012. Tillage practice had no significant effect on grain yield for either planting configuration. Grain yield was increased by approximately 1 Mg ha-1 for both row configurations when stover was harvested, presumably because of more efficient nutrient cycling.
See more from this Division: SSSA Division: Soil & Water Management & Conservation
See more from this Session: Bioenergy Crops, Biomass Production, and Soil and Environmental Quality

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