Those that do such as poison ivy and poison oak can be avoided. They also fought fires and removed poison oak. It produces the irritant urushiol much like its close relatives poison sumac and poison oak. Shrubs such as Oregon grape, honeysuckle, blue elderberry, and Pacific poison oak also grow here. Effects of poison oak are similar to those of poison ivy. The park includes substantial thickets, isolated examples, and mixed ground cover of western poison oak. Poison oak is found throughout the area. Poison oak is found in the training areas. The Ohlone people used the leaves to treat poison oak dermatitis. This includes from sunburn, insect bites, poison ivy, poison oak, or other mild skin conditions. The south-facing slopes primarily consist of grasses, poison oak, sagebrush, and occasional live oak trees. Native Americans used red alder bark to treat poison oak, insect bites, and skin irritations. Western poison oak is a common associate in the California Coast Ranges. Poison oak is also an important member of the native plant habitat community. Atlantic poison oak can be found growing in forests, thickets, and dry, sandy fields.