An evaluation of chemical repellents and Vexar bud caps to reduce winter deer and elk browsing on conifer seedlings in northern Idaho

Abstract

Wintering deer and elk can cause extensive browsing damage to forest plantations. This study was undertaken to identify the cost-effectiveness of two repellents (Plantskydd and Deer-Away BGR Liquid) and Vexar bud caps in reducing browse damage to conifer seedlings. Three plantations located on traditional winter range were selected for the study. The 3 sites were rated by pellet group counts as either elk range, deer range, or both elk and deer range. Treatments were applied to each site in the fall of 2000 in a randomized block design. Trees were then surveyed for damage 5-6 months later once snowmelt had occurred and the animals had migrated to higher elevations. All 3 treatments were equally effective in reducing terminal browse damage by up to 42% when compared to controls on the elk range and deer range sites. However, the site with equal deer and elk use received low browse pressure and no treatment differences for terminal damage were detected. The results of this study should be interpreted with caution, as the winter of 2000-01 was relatively mild in northern Idaho, resulting in a snowpack of 50% of normal. Thus, browse pressure may also have been less than normal. Nevertheless, the 3 treatments tested appear to be effective in reducing both deer and elk winter browsing of conifer seedlings at low to moderate levels of browsing pressure.