The association between grazing and woody plant invasion has been well documented, but mechanisms of the effects of grazing on woody plant establishment and survival are less clear.
Grazing can have direct and indirect effects on grass and woody plant ratios.
The presence of grasses may influence woody plant establishment, growth, and development either directly, via interference, or indirectly, by influencing the fire regime. Walker et al. Once grass aboveground production was reduced below a threshold, succession toward woodland would occur. Reduction of herbaceous biomass and litter can reduce fire frequency and intensity, which may further allow the establishment of woody plants. M odels relating grazing to increased woody plant density and experimental evidence that grazing promotes woody plant establishment, survival, or growth, will be presented in following web pages.