GRAZING OF WINTER CORN BY THE RABBIT (ORYCTOLAGUS CUNICULUS (L.)

Observations on winter corn fields being severely grazed by rabbits showed that there was usually a typical pattern of damage when the source of the rabbits was from one direction. The part of the field nearest the source of rabbits was grazed for a long period and usually failed, the part farthest from the source of rabbits was grazed lightly or not at all and usually yielded well and the central section was intermediate. The effect of severe grazing was to delay plant establishment by retarding or preventing the formation of secondary roots and tillers, so that many plants ultimately died and the survivors were small and backward. Small plots protected by wire netting were used to demonstrate and investigate the effects of grazing, but there was no evidence that the shelter provided by the netting itself in the absence of rabbits directly improved growth within the cages. Artificial defoliation, unless it was very drastic, was not an adequate substitute for rabbit grazing, though this technique was used to confirm a field observation that oats were more susceptible than wheat to this type of damage. Some of the practical implications of the observations and experiments are discussed.