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 pains, stomach pain, purifying blood, and to expel afterbirth (California Ohlone)
          • Stems used to keep pierced ears from closing, or as ear decoration (California Pomo)
          • Roots used 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
                • Found on steep streambanks and trailside or roadside banks, rather than open ground

                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?.