Six Years of Stover Removal: Effecting Yield, Fertility, and Soil Physical Properties.

Six Years of Stover Removal: Effecting yield, fertility, and soil physical properties

Nicholas Bero, Francisco Arriaga, Matthew D. Ruark

Abstract

Stover removal from fields is being utilized more often as a source to produce biofuels. The effect that removing corn stover residue from agricultural fields has on yield, carbon, phosphorus, nitrogen, potassium and soil physical properties has not been extensively studied. Therefore, a field experiment was established in Wisconsin in 2009 at two locations on differing soil types to determine the effects on yield, soil fertility, and physical properties. The studies were located at the Arlington Research station on a Plano silt loam (fine-silty, mixed, superactive, mesic typic argiudaoll) and at the Lancaster Research Station on a Fayette silt loam (fine-silty, mixed, superactive, mesic typic hapludalfs) on a 6-10% slope. Three rates of stover removal were applied at 0, 50%, and 100% (S0, S50, and S100 respectively) at each location. Additionally, each stover removal plot was split with six nitrogen (N) rates of 0, 56, 112, 168, 224, and 280 kg N ha^-1. Starter fertilizer (0-23-31) at a rate of 224 kg ha^-1 was added each year at planting to supply phosphorus (P) and potassium (K). Soil samples were taken at planting to be assessed for nitrate (NO₃-N) and ammonium (NH₄-N). Soil samples taken after harvest were assessed for % organic matter (OM), P and K. Grain yield was greatest in the S100 and S50 rates. Soil NO₃-N was influenced mostly by N rate applied, however the least NO₃-N was in the recommended optimum rate of 168 kg N ha^-1.  Stover removal reduced soil test P and K at both locations however OM was only reduced at the Lancaster site.