Obligate seeding species of ceanothus produce several times the number of seeds as sprouting ceanothus plants. They observed no evidence of decline in seed production with age of shrub up to 86 years. Average annual seed production ranged from 0 seeds up to 21,092 seeds per plant. Seed production requires flower pollination and is therefore dependent on insect populations. Increasing fire severity resulted in better and earlier germination of desert ceanothus seeds compared with chamise seeds and sprouts.
Early mortality is often high.
Desert ceanothus is a chaparral species that grows in several different community types in several geographic locations, each with specific site characteristics. California chaparral is characterized by a Mediterranean climate with cool, moist winters, and hot, dry summers. In general, obligate-seeding species such as desert ceanothus increase in abundance, diversity and longevity with increasing aridity. Ceanothus greggii var. Ceanothus greggii var.