Coffee Fern :

Coffee Cliffbrake
Pellaea andromedifolia
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
Brake Family (Pteridaceae)
Perennial herb
- Grows from long, branched rhizomes (horizontal underground stems)
Fronds
- Triangular blade is compound (divided into leaflets), with usually 3 levels of division (3-pinnate)
- Leaflets are green to purplish, rounded, and may be notched at tip
- Stalks (petioles) are dark brown to black, smooth, and wiry
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 in the curled-under margins of leaflets
- Have no indusium (plural: indusia), a tissue flap sometimes covering sori

Distribution

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

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

Name Derivation

Pellaea (pel-EE-a) – from the Greek pellaios, “dark,” referring to the dark stems and the dark color of mature fronds
andromedifolia (an-dro-me-di-FO-lee-a) – has fronds like the bog rosemary (Andromeda polifolia), itself named after Andromeda, a princess from Greek mythology, who was chained to a rock as an offering to a sea monster and rescued by Perseus
Coffee – refers to the dark color of the mature leaflets and perhaps to their shape, reminiscent of a coffee bean

Notes

Watch this short video showing fern reproduction in action (KQED 2024)
Grows new fronds in the wet season, remaining into the following year
New growth is bright green; fronds darken as they age becoming purple-red or brown
Deer resistant

ID Tips

The 2 other Edgewood ferns in the Brake family – goldback fern (Pentagramma triangularis ssp. triangularis) and California maidenhair fern (Adiantum jordanii) – also have dark-brown to black, smooth, wiry stems, but each has distinct leaflets

At Edgewood

Found in partially-shaded chaparral and similar dry, rocky places
- See iNaturalist for observations of this plant
Coffee fern will tolerate more sunshine than other Edgewood ferns

Specific References

American Fern Society. About Ferns.

KQED San Francisco. 2024, April 16. Watch ferns get freaky [Video]. Deep Look. YouTube.

Prigge, B.A., and A.C. Gibson. 2013. Pellaea andromedifolia. A Naturalist’s Flora of the Santa Monica Mountains and Simi Hills, California. Web version, hosted at Wildflowers of the Santa Monica Mountains National Recreation Area. United States Department of Interior, National Park Service.

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

General References

Calflora Database. 2014. Berkeley, California.

Calscape. 2018. California Native Plant Society.

Corelli, T. 2004. Flowering Plants of Edgewood Natural Preserve (2nd. ed.). Monocot Press, Half Moon Bay, California.

Elpel, T.J. 2013. Botany in a Day: The Patterns Method of Plant Identification. HOPS Press, Pony, Montana.

Harris, J.G., and M.W. Harris. 2013. Plant Identification Terminology: An Illustrated Glossary. Spring Lake Publishing, Spring Lake, Utah.

Keator, G. 2009. California Plant Families. University of California Press, Berkeley and Los Angeles, California.

Regents of the University of California. Jepson eFlora. Jepson Herbarium. University of California, Berkeley.