Cut the plywood into small pieces (approx 12"x12") and place them in separate locations. Fathead males are territorial and chase other fish away from the nest. So isolated or smaller separate spots are much more productive than one big open area. Some fathead raisers will take the smaller boards (cedar shingles) and put or pound them into the pond bank under water at a fairly close angle (30-45 deg)to the bottom. One fish will use each board for spawning.
