[calscape.org] Range, Habitat: Pleasant Valley Mariposa Lily (Calochortus clavatus var. avius) is a rare native perennial herb that grows in Central California, primarily in the Sierra Nevada Foothills region. It tends to grow in rocky slopes and open areas, at elevations from 0-5900 feet. (link added by Mary Ann Machi)

[wildflower.org] Characteristics: Duration: Perennial Habit: Herb Fruit Type: Capsule Size Notes: Branched stem up to about 3 feet tall. Leaf: Leaves up to about 8 inches long, withering by anthesis. Bloom Information Bloom Color: Yellow Bloom Time: May , Jun , Jul Bloom Notes: With reddish brown blotches and hairs near base of petals. (link added by Mary Ann Machi)