LOSSES TO THE CORN CROP CAUSED BY LEAF INJURY

The corn planit as it is grownl in the corn belt is subject (1) to accidental injuries by man and his implements; (2) to destruction of tissues by insects and rodents; anid (3) to rough treatment by lnature in the tearing and twistinig by strong winds, and in the beating and bruising action of rain and hail. This report deals with losses due to mutilationis of the type caused by hailstorms. Unfortunately hail does not injure certain rows of corn alnd leave the adjoining rows uniinjulred so that losses can be accurately compared and measured. Definite iniformation of this kind cani be obtainied onlly from planned experimelnts. It is difficult if not impossible, however, to treat corni plants artificially in a way that accurately duplicates the injury caused by natural hailstorms. Notwithstandinig the elemenit of inaccuracy, experiments of the type here described are believed to be the best means of extending our knowledge of the degree of functional derangement due to injuries of a definite type and severity.