A replicated corn trial in east-central Iowa revealed that both Vitazyme and liquid fish, and the products combined, increased the yield of corn grain significantly — Vitazyme alone and the two products together at P = 0.06, and fish alone at P = 0.05 — with the combined products not showing a synegistic effect. These yield increases were 7.8, 9.0, and 7.6 bu/acre for the Vitazyme, fish, and combined treatments, respectively. Plant population was not affected by either material, but grain moisture was greater than the control for the combined products by 0.81 percentage point at P =0.05.