Roadless Areas
Home/Species/ California Swordfern

Polystichum californicum

(D.C. Eat.) Diels

California Swordfern

G4Apparently Secure Found in 2 roadless areas NatureServe Explorer →
G4Apparently SecureGlobal Rank
UnknownThreat Impact
Identity
Unique IDELEMENT_GLOBAL.2.137580
Element CodePPDRY0R060
Record TypeSPECIES
ClassificationSpecies
Classification StatusStandard
Name CategoryVascular Plant
Endemicoccurs (regularly, as a native taxon) in multiple nations
KingdomPlantae
PhylumFilicinophyta
ClassFilicopsida
OrderFilicales
FamilyDryopteridaceae
GenusPolystichum
Other Common Names
California Sword Fern (EN) California Sword-fern (EN) Polystic de Californie (FR)
Concept Reference
Kartesz, J.T. 1994. A synonymized checklist of the vascular flora of the United States, Canada, and Greenland. 2nd edition. 2 vols. Timber Press, Portland, OR.
Conservation Status
Rank Method Rank calculation - Biotics v2
Review Date2025-01-27
Change Date1989-04-20
Edition Date2025-01-27
Edition AuthorsSoteropoulos (2025)
Threat ImpactUnknown
Range Extent200,000-2,500,000 square km (about 80,000-1,000,000 square miles)
Number of Occurrences81 - 300
Rank Reasons
Polystichum californicum is a wide-ranging, perennial, evergreen fern in a variety of habitats occurring in western North America from southwestern British Columbia, Canada south in the United States to California where it is restricted to the Coast Ranges and Sierra-Cascade axis. There are over 90 occurrences rangewide which face threats from mining, road construction, logging and wood harvesting, recreational activities, collection, diseases, and habitat shifting. Little is known about trends, but with a large range extent and large number of occurrences, abundant habitat, broad habitat preferences, and no obvious intrinsic vulnerabilities, this species is considered apparently secure.
Range Extent Comments
Polystichum californicum occurs in western North America from southwestern British Columbia, Canada south in the United States to California where it is restricted to the Coast Ranges and Sierra-Cascade axis and most abundant in the North Coast Range north of San Francisco (FNA 2002). Range extent was estimated to be over 260,000 square kilometers using herbarium specimens, photo-based observations, and NatureServe Network occurrence data documented between 1994 and 2025 (GBIF 2025, iNaturalist 2025, NatureServe 2025, SEINet 2025).
Occurrences Comments
By applying a 1 km separation distance to herbarium specimens, photo-based observations, and NatureServe Network occurrence data documented between 1994 and 2025, it is estimated that there are over 90 occurrences rangewide (GBIF 2025, iNaturalist 2025, NatureServe 2025, SEINet 2025).
Threat Impact Comments
Although threats are not widely documented, this species is threatened by habitat fragmentation and declining habitat quality from mining, road construction, logging and wood harvesting, recreational activities (e.g., rock climbing, trampling), collection, diseases (potentially root rot (Phytophthora cinnamomi), fungi (leaf blister [Taphrina spp.], dry rot [Fusarium spp.], rusts [Milesia spp.]), bacteria (Pseudomonas sp., Xanthomonas sp.) and nemotodes (Aphelenchoides fragariae)), habitat shifting (increased temperatures and reduced precipitation), and other threats in some places (COSEWIC 2023, NatureServe 2025), though there is insufficient data, including anecdotal accounts, to understand scope and severity of threats for this species.
Ecology & Habitat

Habitat

Polystichum californicum grows "on forest floor in southern part of range and in rock crevices at cliff bottoms (most commonly andesite) to north" at elevations ranging from 100 to 850 meters (FNA 1993). In California, it is found in woodlands and along streambanks to rocky open slopes (Jepson 2025). In Canada, it occurs exclusively on limestone cliffs (COSEWIC 2023).
Terrestrial Habitats
Forest/WoodlandCliff
Palustrine Habitats
Riparian
Other Nations (2)
United StatesN4
ProvinceRankNative
OregonS2Yes
WashingtonS1Yes
CaliforniaSNRYes
CanadaN1
ProvinceRankNative
British ColumbiaS1Yes
Threat Assessments
ThreatScopeSeverityTiming
3 - Energy production & miningUnknownSerious or 31-70% pop. declineModerate (short-term)
3.2 - Mining & quarryingUnknownSerious or 31-70% pop. declineModerate (short-term)
4 - Transportation & service corridorsUnknownExtreme - seriousUnknown
4.1 - Roads & railroadsUnknownExtreme - seriousUnknown
5 - Biological resource useUnknownUnknownHigh (continuing)
5.2 - Gathering terrestrial plantsUnknownUnknownHigh (continuing)
5.2.1 - Intentional use (species being assessed is the target)UnknownUnknownHigh (continuing)
5.3 - Logging & wood harvestingUnknownUnknownHigh (continuing)
6 - Human intrusions & disturbanceUnknownUnknownHigh (continuing)
6.1 - Recreational activitiesUnknownUnknownHigh (continuing)
8 - Invasive & other problematic species, genes & diseasesUnknownUnknownUnknown
8.1 - Invasive non-native/alien species/diseasesUnknownUnknownUnknown
8.1.2 - Named speciesUnknownUnknownUnknown
11 - Climate change & severe weatherLarge (31-70%)UnknownHigh (continuing)
11.1 - Habitat shifting & alterationLarge (31-70%)UnknownHigh (continuing)

—

Plant Characteristics
DurationPERENNIAL, EVERGREEN
Economic Value (Genus)No
Roadless Areas (2)
Oregon (2)
AreaForestAcres
FairviewUmpqua National Forest7,417
Gordon MeadowsWillamette National Forest9,463
References (8)
  1. COSEWIC. 2023. COSEWIC assessment and status report on the California Sword Fern <em>Polystichum californicum</em> in Canada. Committee on the Status of Endangered Wildlife in Canada. Ottawa. x + 32 pp. Online. Available: https://www.canada.ca/en/environment-climate-change/services/species-risk-public-registry/cosewic-assessments-status-reports/california-sword-fern-2023.html (accessed 2025).
  2. Flora of North America Editorial Committee (FNA). 1993a. Flora of North America north of Mexico. Vol. 2. Pteridophytes and gymnosperms. Oxford Univ. Press, New York. xvi + 475 pp.
  3. Global Biodiversity Information Facility (GBIF). 2025. Global Biodiversity Information Facility (GBIF) data portal. Online. Available: https://www.gbif.org/ (accessed 2025).
  4. iNaturalist. 2025. Online. Available: https://www.inaturalist.org (accessed 2025).
  5. Jepson Flora Project (eds.) 2025. Jepson eFlora. Online. Available: https://ucjeps.berkeley.edu/eflora/ (accessed 2025).
  6. Kartesz, J.T. 1994. A synonymized checklist of the vascular flora of the United States, Canada, and Greenland. 2nd edition. 2 vols. Timber Press, Portland, OR.
  7. NatureServe. 2025. NatureServe Network Biodiversity Location Data. NatureServe, Arlington, Virginia.
  8. Southwest Environmental Information Network (SEINet). 2025. Collections Databases. Online. Available: https://swbiodiversity.org/seinet/collections/index.php (accessed 2025).