MOUSE DAMAGE, A SERIOUS PROBLEM FOR THE VIRGINIA APPLE INDUSTRY

The 1972 Apple and Peach Tree Survey indicated that there were 1.6 million apple trees in Virginia. Dr. J. B. Bell and Dr. J. M. Johnson report that based on information from the Statistical Reporting Service and the Economic Research Service that the average per year market value of the 1973-74-75 Virginia Apple crop was $109,160,000. This value consists of the farm value of $28 million plus packing, storage, processing, and other marketing services. It is estimated that mouse damage to apple trees reduces the output in Virginia by 10% per year or a potential loss of $11,000,000 annually for the years 1973-75. From 1967-74, the Virginia Agricultural Foundation provided $50,576 for mouse control research in Virginia. The original grant of $26,576 was from July 1, 1967 through June 30, 1970. That research was directed at determining if pine voles were developing a resistance to endrin, studying orchard cover crops and their inter-relationship with control. Dr. Ryland E. Webb reports that genetic resistance to endrin was developing, this being the first case of a mammal becoming resistant to a poison in its natural habitat. Gophacide and Chlorophacinone were studied with the latter showing more promise