Effect of Corn (Zea mays L.) Stover Mulch on No‐Tillage Corn Yield and Water Infiltration1

Abstract

AbstractCorn was grown for 3 years on Wooster silt loam, a soil on which the yield response of corn to cultivation exceeds that attributable to weed control. Treatments included conventional preplant tillage (plowing, disking) and no preplant tillage with three corn stover residue levels, 5% cover (stover removed), 45% cover (stover left in place), and 70% cover (double level of stover). Except for the first year when the tilled plots were not cultivated, grain yields with 45% cover (6,170 kg/ha) equalled the tilled check (5,970 kg/ha). Yields of treatments with 5% cover were significantly lower (4,770 kg/ha) than the tilled treatment and significantly higher with 70% cover (6,625 kg/ha). Soil moisture determined with gypsum blocks during the last 2 years was greater with increasing amounts of soil cover during the growing season. Soil cover did not increase during the experiment, even on treatments receiving double residue. At the end of the third year, water infiltration as determined with a sprinkling infiltrometer was significantly greater with 80% cover than for the other treatments. Results from these experiments indicate that mulch protection which may be readily available from previous crop residues is necessary to maintain no‐tillage corn grain yields on this and similar areas of Wooster silt loam. The beneficial effects of the mulch seem to be associated with increased soil moisture.