Factors Affecting Blue Oak Sapling Recruitment

We used logistic regression to identify environmental and management history factors associated with blue oak (Quercus douglasii) sapling recruitment. Recent canopy gaps caused by natural mortality or clearing were positively associated with sapling recruitment. Plots with very high or low levels of tree canopy cover were less likely to have saplings than those with intermediate canopy cover levels. Across all locations, and within grazed locations, browsing intensity was negatively associated with sapling presence. Other factors significantly correlated with sapling recruitment include shrub presence, insolation, soil available water-holding capacity, fire, plot altitude, precipitation, and potential evapotranspiration.