Adiantum jordanii
California maidenhair
Photo by Chez Brungraber
Family: Pteridaceae · Type: Herb · Native
Adiantum jordanii (California maidenhair) is a native California herb in the Pteridaceae family, recognized by elevation limit, spore cluster size and yellowish exudate.
California maidenhair is a native perennial fern found in California's Foothills and Plains bioregion in shaded hillsides and moist woodland at elevations below 1,600 meters. Its fronds feature distinctive red-brown to nearly black stalks 20 to 50 centimeters long with delicate, intricately divided blade structures. Growing with elegant, arching foliage, this fern has 2 to 3-pinnate leaves with small pinnules that have less than 4 irregular lobes. Its leaf segments are characterized by converging margins at 90 to 180 degree angles, with a unique midvein that forks into nearly equal branches. The fern produces sporangia with yellowish exudate, forming 1 to 3 sori per pinnule that are generally more than 5 millimeters long.
Identification and appearance
Key characters: 3 sympatric species; elevation limit, spore cluster size and yellowish exudate are diagnostic
Habitat and range
Habitat: Shaded hillsides, moist woodland
Elevation: < 1600 m
California counties: San Luis Obispo, San Mateo, Santa Barbara, Riverside, San Diego, Ventura, Santa Clara, Placer, San Benito, Alameda, Los Angeles, El Dorado, Orange, San Bernardino, Nevada, Butte, Contra Costa, Fresno, Humboldt, Lake, Marin, Mariposa, Mendocino, Monterey, Napa, Santa Cruz, Solano, Sutter, Trinity, Tuolumne, Tehama, Calaveras, Sonoma, Amador, Glenn, San Joaquin, Sacramento, San Francisco, Merced, Colusa, Shasta, Stanislaus, Yolo, Yuba, Kern
Outside California: Oregon, Baja California
How to tell it apart
vs Polystichum: Adiantum has fan-shaped leaflets on black stems; sword ferns have narrow pointed segments on brown stems.; vs Pellaea: Feel the leaflet - Adiantum is thin and delicate, Pellaea is thick and leathery.; vs Thalictrum: Adiantum has spore cases under rolled leaf edges; meadow-rue has flowers and seeds, not spores.; vs Polypodium: Adiantum has fan-shaped leaflets with spores under margins; polypody has elongated segments with round sori.; vs Pentagramma: Adiantum leaflets are thin and delicate; goldback fern leaflets are thicker with powder underneath.
Frequently asked questions
Is Adiantum jordanii native to California?
Yes. Adiantum jordanii is native to California (recorded as native).
Where in California does Adiantum jordanii grow?
Adiantum jordanii occurs in San Luis Obispo, San Mateo, Santa Barbara, Riverside, San Diego, Ventura, Santa Clara, Placer and other counties, at elevations of < 1600 m.
What plant family does Adiantum jordanii belong to?
Adiantum jordanii is in the Pteridaceae family, genus Adiantum.
What habitat does Adiantum jordanii grow in?
Adiantum jordanii grows in Shaded hillsides, moist woodland.
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.