California Polypody

Polypodium californicum
NATIVE

Description (Jepson, PlantID.net)

• Fern (Polypodiopsida) 
  • Ferns are a group of vascular plants that produce spores (reproductive cells)
    • Produce no flowers or seeds
    • Fossil records date back almost 400 million years, versus 130 million years for flowering plants
• Polypody Family (Polypodiaceae)
• Perennial herb
  • Summer deciduous
  • Grows from rhizomes (horizontal underground stems)
• Fronds
  • Deeply lobed (pinnatifid) or compound (divided into leaflets), with 1 level of division (1-pinnate)
  • Leaflets are finger-like
    • Fleshy to leathery, with serrate margins
    • Division incomplete (pinnatifid) with leaflet tissue continuous along the midrib
• Sori
  • Sori (singular: sorus) are clusters of spore-producing, sac-like structures called sporangia (singular: sporangium)
    • Sporangia sacs split open to catapult mature, microscopic spores, which are wind dispersed
  • Located on the underside of leaflets in parallel rows, either side of the midrib
  • Have no indusium (plural: indusia), a tissue flap sometimes covering sori

Distribution

• Native to California
  • Grows on coastal bluffs, in chaparral and mixed evergreen forests, in shaded canyons, along streambanks, north-facing slopes, roadcuts, and cliffs
  • See Calflora for statewide observations of this plant
• Outside California, grows in Baja California, Mexico, but confined to western North America
• Grows at elevations to 5,000 ft.

Uses (San Mateo County Parks prohibits removal of any natural material)

• Native people
  • Juice of the roots used as a rub for rheumatism and on sores as an antibiotic
  • Infusion of roots used as an eyewash

Name Derivation

• Polypodium (Pol-ee-PODE-ee-um) – from the Greek poly, “many,” and pod, “foot,” because the fronds rise from many points along the creeping rhizome

ID Tips

• May be confused with western sword fern (Polystichum munitum), the only other fern at Edgewood whose fronds have one level of division, but western sword fern is not found trailside at Edgewood

At Edgewood

• Found in woodlands
  • Look for it on the boulder at the Sylvan trail waterfall
  • See iNaturalist for observations of this plant

See General References

Specific References

American Fern Society. About Ferns. Resources.

Pai, A. 2018, Dec. 28. Fantastic ferns and where to find them. Bay Nature.

U.S. Forest Service. What are ferns? Forest Service. United States Department of Agriculture.