A tephritid fruit fly (Procecidochares sp.) induces galls covered with whitish pubescence on rabbitbrush (Chrysothamnus nauseosus). The adult tephritid flies emerge in the late spring or early summer and mate soon afterward. Females oviposit one to six eggs in a bud causing the immature leaves to fuse together at the base creating a larval chamber. The eggs overwinter and hatch in the spring. The larvae feed on the leaves forming the chamber. These hairy bud galls were on rabbitbrush at Manzanita Lake in Lassen Volcanic National Park.