Corn Response to Seed‐Row Residue Removal

Abstract No‐till corn ( Zea mays L.) yields in the central Corn Belt often are limited by slow soil warming caused by surface crop residues. A 3‐yr experiment with a split‐plot design was conducted near Ames, IA, to determine corn response to seed‐row residue removal. Whole‐plot treatments were a factorial combination of two tillage systems (no‐till and moldboard plow) and three residue types (corn, soybean Glycine max (L.) Merr., and fiberglass insulation). Residue was removed from bands of various widths (0, 8, 16, 32, and 76 cm) centered on the seed row for five split‐plot treatments. Corn seedlings reached 50% emergence 0.5 d earlier in plots with soybean residue than in those with corn residue. No‐till seedlings reached 50% emergence 0.8 d sooner and 50% tasseling 0.9 d sooner than in the mold‐board‐plow system. Residue removal from the seed row had greater effects on plant growth and yield than either tillage or residue type. Seed‐row residue removal reduced days to 50% emergence and tasseling, increased plant height, decreased grain moisture and barrenness, and increased yield. Removing residue from a 16‐cm wide band resulted in corn yields that were only 3% less than those from bare soil. Plant responses to width of the residue‐free band were described by logarithmic functions. Seed‐row residue removal may allow a compromise between erosion protection and crop yield.