Vegetation and White-Tailed Deer Responses to Herbicide Treatment of a Mesquite Drainage Habitat Type

Abstract

A honey mesquite drainage habitat (20% of a 1,215-ha study pasture) was aerially sprayed with 1.1 kg/ha of 2,4,5-T + picloram in the spring. Adjacent habitats (blackbrush acacia uplands, creeping mesquite flats, blackbrush acacia-dominated mixed brush, and creeping mesquite-mixed brush) were not sprayed. Discriminant treatment of the honey mesquite drainage habitat did not cause consistent differences in white-tailed deer use of that habitat nor did it change deer use of the pasture containing the sprayed drainage based on average daily fecal accumulation rates for 22.5 months after herbicide application. Lack of differences in deer use between sprayed and unsprayed habitats were attributed to minor impacts of sprays on forb populations during the study period, retention of ample cover screen for deer, and increased abundance of grasses on sprayed areas which presumably reduced use of preferred deer food items by cattle.