Management of warm-season annual grass residue on annual ryegrass establishment and production

Early-season forage production of annual ryegrass (Lolium multiflorum Lam.) is reduced in the southeastern USA when established no-till rather than with conventional tillage. We hypothesized that annual warm-season grass residue interferes with seedling establishment under no-till. In a two-year study, we evaluated six strategies for managing residue from warm-season annual grass on annual ryegrass establishment, forage production, and soil moisture. Treatments were (i) no herbicide, mow, and leave residue; (ii) tillage 30 and 7 d before planting; (iii) apply glyphosate [isopropylamine salt of N(phosphonomethyl)glycine] 30 d before planting, mow, and leave residue; (iv) apply glyphosate 7 d before planting, mow, and leave residue; (v) apply glyphosate 7 d before planting, apply additional residue from twice the plot area (i.e., three times the other residue treatments); and (vi) apply glyphosate 7 d before planting, burn residue 1 d before planting. Better stands and more forage production at first harvest of annual ryegrass were obtained by spraying and burning residue (two-year average of 96% stand and 0.92 Mg ha^-1 yield at the first harvest) or spraying 30 d before planting (92% stand, 0.92 Mg ha^-1) than when annual ryegrass was planted into a 3x residue (55% stand, 0.24 Mg ha^-1). Soil moisture at planting did not cause differences in stand establishment among treatments. We conclude that managing residue during no-till establishment by controlling warm-season annual grasses and burning or controlling warm-season annual grasses 30 d before planting can improve stands and forage production of annual ryegrass.