Fig. 2. Effect of plant density and removal on biomass yield for three corn hybrids. R₀, R₁, R₂, and R₃ are no removal and removal of alternate plants at vegetative, tasseling, and early grain-filling stages of growth, respectively. Data points represent plant densities after thinning. Results are average of 2 yr except for 2000. L and Q represent linear and quadratic response, respectively. *Significant at P = 0.05; **Significant at P = 0.01.