Monday, November 13, 2006 - 2:15 PM

Soil Nutrient Removal by Ryegrass Cover Crop after Poultry Litter Application.

M.L. Futrell, R.A. Gilfillen, B.B. Sleugh, J.M. Johnson, and W.T. Willian. Western Kentucky Univ, 1906 College Heights Blvd #41066, Bowling Green, KY 42101-1066

Cover crops are generally used in crop production to protect the field from sediment losses.  However, in this study a ryegrass cover crop was used in hopes of mining excess nutrients from soil after poultry litter application.  This study was conducted during the 2005-06 growing season.  Soils were sampled to a depth of 15 cm immediately before ryegrass harvest.  A randomized split block design was used with 4 treatments.  Blocks were based on no cover crop vs. ryegrass cover crop.  Fertility treatments were: N rate of poultry litter (NPL), P rate of poultry litter only (PPL), P rate of poultry litter with supplemental inorganic N (NPPL), and inorganic fertilizers (I).  Soils were analyzed for nutrient content, organic matter, CEC, and pH.  Significant differences were seen at the p<=0.01 level for available nutrients of P, K, Cu, Zn, and Na.  No significant differences were seen in pH, Organic Matter, CEC, or other available nutrients.  In comparison of these nutrients, the NPL treatment was higher than all other regardless of cover crop or no cover crop.  However, no differences were observed based on cover crop vs. no cover crop treatments.