Influence of thorns and tannins on white-tailed deer browsing after mowing

Abstract

We used caged and uncaged plants to compare shoot growth, biomass, spinescence, nutrient, and tannin content of blackbrush acacia ( Acacia rigidula Benth.), honey mesquite ( Prosopis glandulosa Torr.), and spiny hackberry ( Celtis pallida Torr.) 6 and 12 weeks after mowing, and estimated white-tailed deer ( Odocoileus virginianus Raf.) use of sprouts of each species stripped of spines and unstripped. Blackbrush acacia grew slowly and had more thorns, protein-precipitating tannins, and fiber than honey mesquite or spiny hackberry. Spiny hackberry, a shrub adapted to fertile sites, grew slower and was more physically defended than honey mesquite but lower in tannins than blackbrush acacia, and was the most palatable to deer of the three species. Thorn removal did not alter palatability of the three species to deer.