Effects of Surface Straw on Interrill Runoff and Erosion of Grenada Silt Loam Soil

ABSTRACT RELATIONSHIPS for interrill runoff and interrill soil loss as a function of weight of surface straw were derived for a Grenada silt loam soil using simulated rainfall of 64 mm/h and a laboratory soil pan of 2.5% slope. Increases in surface straw caused significant exponential decreases in soil loss for an initial 60-min **dry run, a 30-min **wet run the following day, and a final 30-min *Very wet run. Soil loss as affected by percent cover was also investigated using a mulch factor equation MF = exp (bC). Results from this research were described with b = 0.015 as compared to the b value of 0.025 that approximates, according to Laflen et al. (1980), the combined rill and interrill cover relationship given in Agricultural Handbook 537.