Abstract
Acorn germination and seedling survival were studied in three species of foothill woodland oaks. Quercus douglasii and Q. lobata acorns matured in October. These nondormant acorns germinated quickly at favorable temperatures. Quercus agrifolia acorns matured later and germinated more slowly. Acorns placed on the surface of a south—aspect plot lost viability. On a north—facing plot they survived autumn heat and germinated during the winter, but rooted poorly. Acorns buried on either aspect germinated well. Burial by birds and squirrels, important in regeneration, insulates acorns from autumn heat, partially hides them from animals, and ensures rooting. Quercus douglasii seedlings had the greatest drought tolerance. In grass cover on a south—facing soil even they can survive their first summer only during wet years. On north aspects seedlings of several species can survive grass competition over a broader range of climatic conditions. Deer and pocket gophers are important in eliminating seedlings that survive the summer drought.