The following is from a USFS pamphlet.
The Western Black-Legged Tick (Ixodes pacificus) is the only tick of the 49 species occurring in California known to transmit Lyme Disease. The tick has three active stages: Larvae, nymph, and adult. In its immature stages, the larvae and nymphs feed on small rodents such as rabbits, lizards, and birds. Adults feed on larger animals such as deer, dogs, and humans. In all of the stages, the tick feeds by imbedding its mouth-parts into the skin of the host and taking in a meal of blood.
Preliminary studies indicate that white-footed mice and deer may be the primary reservoirs of Lyme disease in California. Larval and nymphal ticks acquire spirochetes from the blood of infected mammals as they feed. Then the infected nymphs and adults transmit the spirochetes to other mammals, including humans. However, in California, only a very small percentage of the ticks tested for Lyme Disease are infected with it.
Adult ticks are most commonly found from December through June, during the part of the year when humidity is at its highest. The adult female is red-brown with black legs and is about 1/8 inch long. Males are smaller and entirely brownish-black. Both are teardrop shaped.
While the Western Black-Legged Tick has been found in 50 of the 58 counties in California, it is most common in the humid coastal areas and on the western slope of the Sierra Nevada. It resides on grasses and brush in both rural and urban settings. They do not fly, jump, or drop from trees. Instead, they climb onto the tips of vegetation, typically along animal and hiking trails, and wait for a host to brush against them, a type of behavior that is known as questing.
To Avoid Them
Tuck pants into boots or socks and your shirt into your pants. Wear light-colored clothing so ticks can be seen easily. Apply insect repellant on pants, socks, and shoes. Avoid trail margins, brush, and grassy areas when in tick country. Check yourself and your children frequently. Prompt removal of ticks may prevent transmission of the disease.
To Remove Them
Use tweezers rather than your fingers. If you must touch the tick, use tissue to protect your hands. Grasp the tick’s mouth parts as close to the skin as possible. Gently pull the tick straight out in a firm and steady manner. Do not twist or jerk the tick. It has harpoon-like barbs and does not screw into the skin. If the mouth parts break off and remain in your skin, consult your doctor. Wash your hands and the site of the bite with soap and water. Apply an antiseptic afterwards.
Courtesy of U.S. Forest Service