Polystichum imbricans
Cliff sword fern
(c) Ed Alverson, some rights reserved (CC BY) · licence
Family: Dryopteridaceae · Type: Herb · Native
Polystichum imbricans (Cliff sword fern) is a native California herb in the Dryopteridaceae family, recognized by no sympatric species.
Cliff sword fern is a California native perennial fern found in rocky montane habitats across northern California mountain ranges at elevations typically ranging from 500 to 2,500 meters. Producing fertile fronds through spring and summer, this fern has dark green, narrow-lanceolate leaves with distinctive dense, overlapping pinnae. Growing with erect to arching fronds 30 to 60 centimeters tall, it develops a robust clumping habit with a short, thick rhizome. Its fronds feature narrow, lance-shaped blades with pinnae that have small, pointed scales at their bases, creating a textured, slightly lustrous appearance. The fern's spore-bearing structures are protected by small, round indusia that are nearly entire to slightly toothed along their margins.
Identification and appearance
Key characters: Geographically isolated; no sympatric species
Habitat and range
California counties: Plumas, Siskiyou, Trinity, Tuolumne, Shasta, Mariposa, Los Angeles, Nevada, Riverside, San Bernardino, Fresno, Lake, Madera, Mendocino, Monterey, Napa, Tulare, Del Norte, San Diego, Placer, Sierra, Santa Barbara, Sonoma, Butte, Tehama, Yuba, Marin, Humboldt, San Luis Obispo, Orange
How to tell it apart
vs Nephrolepis: Polystichum has bristle-tipped teeth and grows in wild habitats; Boston fern has smooth-edged leaflets and escapes from cultivation.; vs Dryopteris: Polystichum fronds feel prickly with bristle-tipped teeth; Dryopteris fronds feel smooth without bristles.; vs Polypodium: Polystichum has shield-shaped spore covers and bristly edges; polypody has naked round spore dots and smooth margins.; vs Struthiopteris: Polystichum has one frond type with bristly teeth; ostrich fern has separate narrow fertile fronds and smooth sterile ones.; vs Athyrium: Polystichum feels prickly and has shield-shaped spore covers; lady ferns feel soft with curved, elongated spore clusters.
Frequently asked questions
Is Polystichum imbricans native to California?
Yes. Polystichum imbricans is native to California (recorded as native).
Where in California does Polystichum imbricans grow?
Polystichum imbricans occurs in Plumas, Siskiyou, Trinity, Tuolumne, Shasta, Mariposa, Los Angeles, Nevada and other counties.
What plant family does Polystichum imbricans belong to?
Polystichum imbricans is in the Dryopteridaceae family, genus Polystichum.
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.