Potentilla hickmanii (called Hickman's potentilla or Hickman's cinquefoil) is an endangered perennial herb of the rose family. This rare plant species is found in a narrowly restricted range in two locations in coastal northern California, in Monterey County, and in very small colonies in San Mateo County. This small wildflower, endemic to western slopes of the outer coastal range along the Pacific Ocean coast, produces bright yellow blossoms through spring and summer. This species was formerly thought to be growing in Sonoma County, but that population has been recently reclassified as another species, Potentilla uliginosa, and is presumed extinct in that county. This plant, along with many other threatened species in the northern California Floristic Province, has been designated as a species meriting protection by the U.S. government, state of California, local governments, and private conservation groups. These designations have led to blueprints for protection of Hickman's potentilla in the form of official endangerment classifications and a species recovery plan, the latter promulgated by the U.S. Fish and Wildlife Service. Description P. hickmanii is a long-lived, rosetted, nonglandular flowering plant with a thick taproot. The stem is prostrate, 5–45 cm long. Blooming occurs between April and August. The hypanthium is 3–6 mm wide, with yellow obchordate petals 6–11 mm in length. Up to 10 inflorescences may present in a single plant. Filaments are typically 1.5 to 4.0 mm in length, while anthers are only about 1.0 mm in size; moreover, the pistils generally number about 10 and the slender styles are about 2–3 mm long. The somewhat subglabrous leaves are pinnately compound into generally six paired, palmately cleft leaflets. These basal leaves range from 6–25 in length with individual leaflets 2–8 mm long and about 2 mm wide. Four to seven leaflets occur per side, in a separated or overlapped configuration. The leaflets are wedge-shaped, typically having three or four teeth (lobes) and originate from about halfway along the leaf stem. The smooth fruits are about 2 mm in diameter and tan in color, looking like miniature watermelon seeds Distribution and habitat P. hickmanii is currently known to occur in two coastal locations. The Federal Register documents colonies on the Monterey Peninsula and at another area in coastal San Mateo County. The Monterey population is within the municipal boundaries of the city of Monterey, growing in a native grassland opening of the Monterey pine forest at an old summer camp