Propane exploders and Electronic Guards were ineffective at reducing deer damage in cornfields

White-tailed deer (Odocoileus virginianus) cause millions of dollars of damage to agricultural crops annually. We tested the effectiveness of propane exploders and Electronic Guards (Pocatello Supply Depot, Pocatello, Id.) for reducing deer damage in cornfields during the silking-tasseling stage of growth. Track-count indices (F₂,₇=0.70, P=0.532), corn yields (F₂,₆=0.14, P=0.873), and estimated damage levels (F₂,₁₂=1.45 P=0.272) did not differ between experimental and control fields. The size (F₂,₁₁=0.08, P=0.924), location (F₂,₉ =0.30, P =0.750), and percent overlap (F₂,₉ =0.46, P =0.644) of use-areas of radiomarked female deer in the vicinity of experimental fields did not differ among before, during, and after 18-day treatment periods. In a related study, we placed propane exploders in cornfields within use-areas of 12 radiomarked female deer. The deer did not react appreciably to the devices: the size (F₂,₁₇=0.08, P=0.921), location (F₂,₂₂=1.37, P = 0.275), and percent overlap (F₂,₁₀ = 0.47, P = 0.636) of deer use-areas did not differ among before, during, and after 14-day treatment periods. We conclude that propane exploders and Electronic Guards have limited potential for reducing deer damage to corn at the silking-tasseling stage.