Influence of Mowing and Herbicide Application on White-tailed Deer Use of Perennial Forage Plantings

Plantings of perennial and biennial forage, such as white clover (Trifolium repens), red clover (Trifolium pratense), and alfalfa (Medicago sativa), commonly are used by managers to increase nutritional resource availability for white-tailed deer (Odocoileus virginianus). Regular mowing and selective herbicide applications are two common practices used to maintain perennial plantings and reduce weed competition. However, there is little information available on how these management activities influence perennial forages or wildlife response. We evaluated the effects of regular mowing on forage production, forage quality, weed coverage, and deer detections as a case study in a perennial forage planting in Tennessee, May–August 2020. We also evaluated deer detections following application of selective herbicides among four fields in Tennessee and North Carolina, October–November 2021. Regular mowing reduced forage availability by 37% and did not increase forage quality or deer use of the food plots. Additionally, regular mowing decreased coverage of clover and alfalfa, which led to increased weed competition by late summer. Deer use did not change the month following selective herbicide application, but we observed a 67% decrease in deer detections the week following herbicide application. Regular mowing was not an efficient strategy to manage perennial forage plantings. We suggest managers maintain perennial forage food plots with selective herbicide applications in spring and fall and by mowing once during the latter portion of the growing season. Selective herbicides may reduce deer use of forage plantings for a few days after application, but use likely returns to normal soon thereafter.