Orobanche vallicola is a species of broomrape known by the common name hillside broomrape. It is endemic to California, where it is an uncommon member of the flora in forests and woodlands. Orobanche vallicola is a parasite growing attached to the roots of other plants, generally Sambucus species. The plant produces a thick, hairy, glandular pinkish stem up to about 40 centimeters tall. As a parasite taking its nutrients from a host plant, it lacks leaves and chlorophyll. The inflorescence is a cluster or branching array of flowers. Each tubular flower is up to 3 centimeters long, yellowish to pinkish and red-veined in color.