Date of this Version
Meadow voles (Crotus pennsylvanicus) and pine voles (Crotus inetorum) cause extensive damage to apple trees by gnawing and girdling trunk and root systems. In 1991, approximately 70% of Vermont's 90 commercial apple producers were using zinc phosphide (ZP) treated cracked corn to manage vole damage. From November 1991 throughout January 1992, 36 confirmed wild turkey deaths were attributed to the broadcast application of ZP treated cracked coin in Vermont orchards. As a result of public concern regarding impacts to nontarget wild turkeys, a working group was formed with representation of various state and federal agencies as well as the apple industry to address this issue and review current vole damage management strategies. Since 1992, statewide voluntary compliance with working group recommendations that included shifting to ZP treated rolled oats have reduced the risk of wild turkey exposure to ZP. In this paper we discuss the effectiveness of the working group recommendations as measured by a mail survey of apple producers as well as a preliminary 4-year analysis of statewide rodenticide sales.