Application of the Variance Method to the Comparison of Grasshopper Baits1

Abstract

The factors to be considered in selecting test plots for toxicity studies were discussed. 12 test baits were used and each was replicated 12 times. The results were treated statistically by the variance method, and the standard error was used in place of the probable error as used by Goulden. Salt added to the basic formula (bran, arsenic and water) decreased the efficiency of the bait. The basic formula to which was added either cane molasses or beet molasses, amyl acetate and salt ranked above the basic formula; however, the difference was not significant. Amyl acetate increased the effectiveness of the bait when beet molasses was added, but not with cane molasses No practical substitute for bran was found. Results were comparable to the amount of bran contained in the bait.