Table 5-5. Analysis two planting dates. of variance of grain and stover yield for the Planting Error Error mean period D.F. mean square square ratio F,, F99 Grain yield First 9 40442 2.21 ns 3.18 5.35 Second 9 18301 Stover yield First 9 411685 1.66 ns 3.18 5.35 Second 9 247991 ns not significantly different