Heidi Myer, Pennsylvania State University, State College, PA, Heather D. Karsten, Department of Plant Science, Pennsylvania State University, University Park, PA, John Tooker, Entomology, Pennsylvania State University, University Park, PA and William S Curran, Plant Sciences Department, Pennsylvania State University, University Park, PA
No-till cover crop systems in the Mid-Atlantic region can pose agronomic and pest management challenges, including: i. plant residue interference with seed placement, ii. poor row closure due to high moisture, and iii. ideal slug habitat, all resulting in reduced yields. Typically, cover crops are terminated one to two weeks before planting, but some farmers are delaying termination until planting or later for soil conservation and soil moisture management. We hypothesized that terminating cover crops at cash crop planting rather than earlier would improve seedbed conditions for planting; extend soil and water conservation benefits of cover crops; and reduce slug habitat damage to the subsequent crop of corn (Zea Mays L.) or soybean (Glycine max L.). The experiment was conducted at the PSU Russell E. Larson Agronomy Research Farm in Pennsylvania Furnace, PA and the South East Agricultural Research and Extension Center in Landisville, PA. Treatments in the corn experiment consisted of rye (Secale cerealL.), crimson clover (Trifolium incarnatum L.), or a rye-crimson clover mix, terminated either early or at corn planting in 18 x 23 m plots in a randomized complete block design with four replications. Treatments in the soy experiment consisted of 34, 67, or 134 kg ha-1 rye planting rate, 67 or 134 kg ha-1 N fertilization rate, terminated either early or at soybean planting in a split-plot design with main plots (18 x 23 m) in a randomized complete block and four replications. Cover crop biomass was determined at early termination and at planting, while slug and beneficial insect populations; soil moisture and temperature, and residue cover were measured throughout the growing season. Slug and insect herbivory on cash crops and stand counts were measured at V2 and V5, and corn and soybean yields were compared.