Describe chaparral, the dense shrubs that grow on Southern California's mountains, and chaparral brush fires.

Chaparral consists of a variety of dense shrubs that grow on Southern California's mountainsides. These plants burst easily into flame, and many types are rejuvenated by fire, with seeds germinating only after there's a fire. The leaves of chaparral plants are coated with oil, which seals in moisture. It is this oil that makes the plant blaze explosively in a brush fire. Chaparral fires burn intensely.