Evergreen with clustered fronds.
Narrowly lanceolate, 10-25 cm long, 0.7-1.5 cm wide; rachis winged with two wax-papery lines, reddish-brown throughout (except the green tip on youngest leaves); pinnae in pairs, egg-shaped to oblong egg-shaped, 5-15 mm long, 3-8 mm wide.
A variable species. Two chromosome races (diploid ssp. trichomanes and tetraploid ssp. quadrivalens D.E. Meyer) were reported from North America (Moran 1982, Wagner et al. 1993), but their distribution in British Columbia is poorly known and requires further study.