Location: Agroecosystem Management ResearchTitle: Corn stover harvest: Likely effects on soil productivity Author
Submitted to: Extension Publications
Publication Type: Experiment Station
Publication Acceptance Date: 8/16/2012
Publication Date: 8/17/2012
Citation: Wortman, C., Varvel, G.E. 2012. Corn stover harvest: Likely effects on soil productivity. Extension Publications. Available: http://cropwatch.unl.edu/web/cropwatch/archive?articleID=4968806. Interpretive Summary:
Technical Abstract: Demand for corn stover for cattle feeding is likely to be especially high this year because of poor rainfed corn performance and because drought stressed pastures and rangeland are likely to be slow to recover in 2013 and stover will be needed to feed cows. Corn stover harvest is addressed in more detail in the recently revised NebGuide 1846 Harvesting of Crop Residues. Many are concerned that occasional stover harvest will reduce yield potential. However, the results of two long term studies conducted by the USDA-ARS at the UNL-ARDC do not suggest a reason for concern for many eastern Nebraska fields and for irrigated land. The soils at the trial sites of silt loam are 2-3.5% soil organic matter. The effect of N rate with 0 or 100% crop residue removal for continuous rainfed corn was higher yield with 120 compared with 60 lb N/ac applied in an ongoing trial initiated in 2000 (Table 1). Residue removal did not have a long term effect on average grain yield (Table 1). Grain yield was generally reduced by residue removal in 2002, 2003, and 2006 but increased in 2005, 2010, and 2011. In an irrigated trial started in 2001, residual removal did not affect yield with no-till but yield was reduced by residue removal with disk tillage (Table 2). Soil organic matter has not been affected by residue harvest. These results are solid evidence that grain yield is not likely to be reduced by occasional residue harvest for medium texture soils in eastern Nebraska, especially with no-tillage. We cannot extend these results to sandy soils, to rainfed conditions in drier parts of the state, and to low organic matter soils.