Perideridia gairdneri
Gairdner's yampah
(c) Matt Lavin, some rights reserved (CC BY-SA) · licence
Family: Apiaceae · Type: Herb · Native
Perideridia gairdneri (Gairdner's yampah) is a native California herb in the Apiaceae family, recognized by small round fruits distinctive.
Gairdner's yampah is a California native perennial found in various bioregions in open grasslands and meadows at elevations up to 1,500 meters. Flowering from May to July, this plant produces white flowers in delicate umbel clusters with multiple small florets spreading in an ascending pattern. Growing with slender stems 30 to 140 centimeters tall, it develops distinctive fusiform roots clustered in groups of two or three. Its basal leaves are complex, featuring pinnate blades up to 35 centimeters long with linear or lanceolate leaflets that can reach 12 centimeters in length. The fruit is small and nearly round, approximately 3 millimeters in diameter with thread-like ribs.
Identification and appearance
Key characters: Geographically isolated; small round fruits distinctive
Habitat and range
California counties: Fresno, Inyo, San Luis Obispo, Los Angeles, Marin, Shasta, Tehama, Mendocino, Solano, Monterey, Santa Cruz, Madera, Tulare, Plumas, Siskiyou, Mariposa, Amador, San Bernardino, El Dorado, Humboldt, Glenn, Nevada, Sierra, Lassen, Tuolumne, Trinity, San Benito, Ventura, Alpine
How to tell it apart
vs Ligusticum: Perideridia grows from tubers in grasslands; Ligusticum grows from taproots in mountain forests.; vs Daucus: Perideridia fruits are rounded with thin ribs; Daucus fruits are bristly and form a bird's-nest cluster.; vs Eriogonum: Eriogonum is in the buckwheat family with papery flowers; Perideridia has carrot-family umbels.; vs Angelica: Perideridia has small rounded fruits; Angelica has large flattened fruits with broad wings.; vs Achillea: Achillea is in the sunflower family with flat-topped flower heads; Perideridia has carrot-family umbels.
Frequently asked questions
Is Perideridia gairdneri native to California?
Yes. Perideridia gairdneri is native to California (recorded as native).
Where in California does Perideridia gairdneri grow?
Perideridia gairdneri occurs in Fresno, Inyo, San Luis Obispo, Los Angeles, Marin, Shasta, Tehama, Mendocino and other counties.
What plant family does Perideridia gairdneri belong to?
Perideridia gairdneri is in the Apiaceae family, genus Perideridia.
Related species
Other California species in the same genus, family, or bioregion.
Sources: Jepson eFlora · Index of California Plant Names · CalPhotos
Last updated 2026-10-07
Data from The California Species Project — 14,000+ California species with verified data from CNPS, CDFW, USFWS, Cal-IPC, and more.