Perideridia californica is a species of flowering plant in the carrot family known by the common name California yampah. It is endemic to California, where it is known from the Central Coast Ranges and a section of the Sierra Nevada foothills. It grows in moist soils, often near streams. It is a perennial herb which may approach 1.5 meters in maximum height, its slender, erect stem growing from cylindrical tubers measuring up to 12 centimeters long....