California Maidenhair Fern

California Maidenhair Fern © DSchiel

Adiantum jordanii

Description (Jepson,

Stems © KKorbholz
    • Polypodiopsida (ferns)
      • A group of early vascular plants that produce spores (no flowers or seeds)
    • Brake / Maiden-hair Family (Pteridaceae)
    • Perennial fern
      • Grows from short creeping rhizomes (horizontal underground stems)
    • Fronds
      • Divided into leaflets (compound) with 2 levels of division (pinnation)
      • Leaflets (leaf-like structures of compound leaf) are round or fan-shaped, slightly lobed, and finely-toothed
    • Stems are dark brown to black, smooth, and wiry
    • Reproduces from spores (a small, usually single-celled, reproductive body)
      • When mature, leaflet margins roll under, hiding 1-5 sori (sacs containing spores)
    • Height generally 8-18 in.


      • Native to California
        • Grows in soil and rock crevices on shaded hillsides and in moist woodlands
        • See Calflora for observations of this plant
      • Outside California, grows from Oregon to Baja California, Mexico
      • Grows at elevations to 3,775 ft.

      Uses (Picking or removing any natural material from public land is illegal)

        • Native people had a variety of uses for California maidenhair fern
          • Decoction of the plant used for internal pain, purifying blood, and expelling afterbirth (California Ohlone)
          • Stems used to keep pierced ears from closing or as ear decoration (California Pomo)
          • Used roots for binding baskets and stems for basket designs

        Name Derivation

          • Adiantum (ad-ee-AN-tum) – from the Greek for “unwettable,” referring to the fronds shedding water
          • jordanii (JOR-dun-ee-eye) – a tribute to Rudolf Jordan, Sr. (1818-1901), a German immigrant to California, who collected this fern and had it identified by German botanist Karl Mueller, who named the species after Jordan
          • Maidenhair – implies fine hairs, which may refer to the slender stems or the many fine roots


            • New fronds grow at the beginning of the wet season and dry up in late fall
            • Host to the fungus-like microorganism Phytophthora ramorum, which causes Sudden Oak Death (SOD)
              • At Edgewood, the 2 species known to be highly susceptible to SOD are coast live oak (Quercus agrifolia var. agrifolia) and Pacific madrone saplings (Arbutus menziesii)
              • For a complete list of known hosts and host associates see USDA Risk Analysis for Phytophthora ramorum, pp.6-9

            ID Tips

              • To distinguish from other Edgewood ferns, look for fan-shaped, delicate leaflets

              At Edgewood

                • Found in woodlands on moist, shaded hillsides and stream banks

                See General References

                Specific References

                  American Fern Society. About Ferns.

                    Anthropology Museum, California State University, Sacramento. Enduring Traditions: Baskets in Native California, a Mobile Classroom Outreach Trunk.

                      California Department of Parks and Recreation. 2019. California Indian Baskets.

                        U.S. Forest Service, United States Department of Agriculture. What Are Ferns?.