Scarification by hydrochloric acid, heat, or mechanical means breaks dormancy. A study was conducted to test the germination capacity of fresh seed of seven chaparral species after exposure to elevated temperatures. It showed that laural sumac and the taxonomically related sugarberry required higher temperatures for germination than all other species tested. Drought sensitivity is a major factor inhibiting recruitment. Germination and growth are favored on sites with summer microshade.
Seedlings are also sensitive to cold.
Insular populations, exposed to the maritime climate, undergo little seasonal fluctuation in the mild temperatures. Populations in Mediterranean and semiarid climates receive 90 percent of annual rainfall from November to April. Parent materials include diorite, shale, sandstone, and sandstone with conglomerate. It is favored on soils with high exchangable potassium levels. Peak abundance occurs on coastal sites with heavy litter layers.