Two of them, Coastal Sage Scrub and Oak Woodland, are intermixed along the west side of campus. The third, Walnut Woodland, covers the hills on the south side. Coastal sage scrub is the most diverse community on campus. Over 150 different species of plants occur in the wildlands, and almost all of them can be found in coastal sage. All of these, and a number of other species, are fragrant, especially in the late spring and early summer.
Fire is a major force that shapes coastal sage scrub.
Most of the species are adapted to fire. Many of the shrubs and trees resprout from underground roots or stems after a fire. About half of Cal Poly's coastal sage burned in August of 1981, and virtually all of it burned at the end of July in 1989. Its current vigorous growth attests to its adaptation to fire. Large tracts of southern California were once dominated by coastal sage scrub.