Variations in elevation, rainfall, temperature, and geology in these ancient mountains provide ideal habitat for over 1,600 species of flowering plants, including 100 native tree species and over 100 native shrub species. The park is also a global center for non-flowering plants, including 450 bryophytes-mosses, liverworts, and a few hornworts. Non-flowering species also include some 50 ferns and fern allies and at least one horsetail.