The Sword Fern is a large perennial that grows from a crown to form spread out of a clump of ferns. The crown consists of a mass of rhizomes buried in reddish-brown scales. Roots explore the soil from the rhizome. In a mature well-established clump the mass of the crown may reach 0.5 m or more in diameter.
Dark green sword fern fronds stand stiffly from the crown. Fronds reach as tall as 1.5 meters and up to 25 cm wide. The upper two-thirds of the frond has numerous narrow, pointed, and toothed leaflets and the bottom third is usually made up of dead material. Near the tip of the frond, the leaflets become progressively shorter. Young unfolding leaves are at first curled like a shepherd’s crook, then gradually unfurl and expand.
On Vancouver Island, the sword fern is dominantly a coastal species, occurring on the whole Island. The range extends across extreme southern B.C. and adjacent Washington, Idaho, and in the southeastern part of the province.
The North American range extends along the coast from Alaska almost to the Mexican border. Generally, sword fern thrives in the shaded humus of the damp to moist conifer forest floor. In very wet forests you may see it perched on a shady rock face.
Sword fern forms a distinctive association with western red cedar on nutrient-rich seepage sites. Fern clumps completely cover the forest floor in the coastal rain forests.