Pentagramma viscosa
Coastal silverback fern, Coastal Silverback Fern
(c) Jason Schock, some rights reserved (CC BY) · licence
Family: Pteridaceae · Type: Perennial · Native
Pentagramma viscosa (Coastal silverback fern) is a native California perennial in the Pteridaceae family, recognized by sticky adaxial surface and recurved margins diagnostic.
Coastal silverback fern is a California native perennial found in southern California coastal and Channel Islands regions in generally shaded, wooded or grassy slopes near the coast at elevations below 850 meters. Flowering time not specified, this fern has distinctive silvery-green fronds with pinnae that feature dense glandular surfaces, creating a sticky texture. Growing with a rhizomatous root system, the fern produces fronds with proximal pinnae 2 to 5 centimeters long and delicate pinnule margins that are slightly recurved at the tips. Its leaf blades are characteristically sticky, covered with dense glands that give the plant a distinctive appearance and texture. The fern's unique glandular surface and coastal habitat make it a notable species in its native ranges.
Identification and appearance
Key characters: 1 sympatric species; sticky adaxial surface and recurved margins diagnostic
Habitat and range
Habitat: Generally shaded, wooded or grassy slopes in proximity to coast
Elevation: < 850 m
Outside California: Baja California
How to tell it apart
vs Pteridium: Pentagramma is small (<30 cm) and stays in rock crevices; Pteridium is tall (>50 cm) and spreads in open areas.; vs Polypodium: Pentagramma fronds are finely divided multiple times; Polypodium fronds are simple with one row of undivided leaflets.; vs Dryopteris: Pentagramma has golden/silver coating underneath; Dryopteris undersides are green with kidney-shaped spore covers.; vs Aspidotis: Pentagramma segments attach broadly; Aspidotis segments are bead-like with edges rolled under to protect spores.; vs Myriopteris: Pentagramma undersides are smooth or waxy; Myriopteris undersides are fuzzy with hairs or scales.
Frequently asked questions
Is Pentagramma viscosa native to California?
Yes. Pentagramma viscosa is native to California (recorded as native).
What plant family does Pentagramma viscosa belong to?
Pentagramma viscosa is in the Pteridaceae family, genus Pentagramma.
What habitat does Pentagramma viscosa grow in?
Pentagramma viscosa grows in Generally shaded, wooded or grassy slopes in proximity to coast.
Related species
Other California species in the same genus, family, or bioregion.
- Pentagramma glanduloviscida — San diego silverback fern
- Pentagramma maxonii — Desert silverback fern
- Pentagramma pallida — Frosty silverback fern
- Pentagramma rebmanii — Rebman's silverback fern
- Pentagramma sp. — Goldback or silverback fern
- Pentagramma triangularis — Goldback fern
- Pteridaceae sp. — Brake family
- Pteris cretica — Cretan brake
- Pteris sp. — Brake
- Pteris tremula — Australian brake
Sources: Jepson eFlora · Index of California Plant Names · CalPhotos
Last updated 2026-09-30
Data from The California Species Project — 14,000+ California species with verified data from CNPS, CDFW, USFWS, Cal-IPC, and more.