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Vegetation responses may be more strongly linked to environmental stochasticity than they are to herbivore density in semiarid rangelands. Although decoupling of vegetation and herbivores by environmental variability has been observed by several researchers, why and how it occurs is unclear. We conducted a decade-long experiment in southwest Texas, U.S.A., to determine the response of vegetation to white-tailed deer (Odocoileus virginianus) densities ranging from low (12 deer/km�) to high (50 deer/km�). Our results provide insight into some of the variables that may underlie the weak linkage between herbivores and vegetation in environments characterized by periodic resource pulses following precipitation events. We found that increasing deer density did not result in a decline in palatable plants or an increase in plants that are less palatable or are resistant to herbivory as predicted by traditional theory. White-tailed deer were primarily browsers during autumn and early winter, and shifted to a diet of primarily forbs during late winter to late spring when precipitation was above average. Deer consumed primarily mast during summer. Reduced browsing during spring and summer allowed woody plants to recover from defoliation during autumn and early winter, which ameliorated effects of deer density. Forbs were highly productive during wet years and virtually absent during dry years. Heat and lack of moisture during late spring caused palatable forbs to senesce before deer could reduce them, even at high deer density. By early summer deer shifted their diets to mast. This also helped to prevent deer from depleting palatable forbs, even at high deer densities. Generalist foraging behavior by deer, asynchronous plant phenology, and strong responses of vegetation to precipitation are among the variables that act to weaken the linkage between deer and vegetation in highly stochastic environments.