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Research on African shrub communities similar to those in South Texas suggests that heavy browsing stimulates regrowth with higher nutritional quality than un-browsed plants. Conversely, shrubs may allocate resources to defenses such as thorns, branching, or secondary compounds rather than to new leaves and twigs in response to herbivory. Based on the optimization hypothesis, our objective was to test the prediction that there may be an optimum white-tailed deer (Odocoileus virginianus) density at which regrowth and nutritional quality of blackbrush acacia (Acacia rigidula), twisted acacia (A. schaffneri), and spiny hackberry (Celtis pallida) can be maintained through browsing. Starting July 2014, we measured shoots and thorns annually on marked stems for each shrub species in 81 hectare enclosures containing 0, 25, 50, and 75 deer per km^2 on each of 2 ranches. A supplemental feeder was present in each enclosure. Each July and October, we removed leaf and twig samples from a different set of plants of each shrub species for nutritional quality analysis. Measurements and samples were taken within the white-tailed deer's browsing zone (50-100 cm from the ground) in each cardinal direction on the plants. The percentage of browsed twig tips increased linearly with increasing deer density from 0% with no deer to over 60% with 75 deer per km^2 . Preliminary results indicated that the number of non-lignified stems initially increased with increasing deer density, peaked at 50 deer per km^2, and then declined from 50 to 75 deer per km^2. Traditionally, managers try to achieve deer densities that are low enough to avoid causing undesirable changes in the plant community. A more efficient approach may be to manage for deer densities that optimize browse quality and quantity.