Polystichum munitum
Western sword fern
(c) Ed Alverson, some rights reserved (CC BY) · licence
Family: Dryopteridaceae · Type: Herb · Native
Polystichum munitum (Western sword fern) is a native California herb in the Dryopteridaceae family, recognized by large size, persistent scales, and leaflets in one plane.
Western sword fern is a native perennial found in northwestern California, northern Sierra Nevada, northern High Sierra Nevada, central western California, northern Channel Islands, Transverse Ranges, and Modoc Plateau, including caves in Lava Beds National Monument, on wooded hillsides and shaded slopes at elevations up to 1,600 meters. While not producing flowers, this fern is distinguished by its impressive fronds reaching 50 to 120 centimeters long, forming dense, arching clusters of dark green foliage. Growing with a robust, upright habit, it develops a distinctive lanceolate blade with pinnae arranged in a single plane, creating a graceful, feather-like structure. Its leaves feature a stipe (stem) that comprises one-fifth to one-half of the blade length, with a base of ovate scales that persist and provide structural complexity. The fern's dense, layered fronds create rich green carpets in forest understories, making it a quintessential indicator of moist, shaded woodland environments.
Identification and appearance
Key characters: 9 sympatric species; distinguished by large size, persistent scales, and leaflets in one plane
Habitat and range
Habitat: Common. Wooded hillsides, shaded slopes, rarely cliffs, outcrops
Elevation: < 1600 m
California counties: San Luis Obispo, San Bernardino, Sonoma, Santa Barbara, San Mateo, Siskiyou, Santa Cruz, Trinity, San Francisco, Mendocino, Monterey, Los Angeles, Alameda, Contra Costa, Del Norte, Humboldt, Marin, Santa Clara, Tulare, Plumas, Sierra, Riverside, Butte, El Dorado, Napa, Nevada, Lake, Shasta, Tuolumne, Calaveras, Yuba, Tehama, Colusa, Mariposa, Ventura, San Diego, Placer
Outside California: to Alaska, Montana, South Dakota, also Guadalupe Island (Mexico)
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 munitum native to California?
Yes. Polystichum munitum is native to California (recorded as native).
Where in California does Polystichum munitum grow?
Polystichum munitum occurs in San Luis Obispo, San Bernardino, Sonoma, Santa Barbara, San Mateo, Siskiyou, Santa Cruz, Trinity and other counties, at elevations of < 1600 m.
What plant family does Polystichum munitum belong to?
Polystichum munitum is in the Dryopteridaceae family, genus Polystichum.
What habitat does Polystichum munitum grow in?
Polystichum munitum grows in Common. Wooded hillsides, shaded slopes, rarely cliffs, outcrops.
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.