Osmundastrum cinnamomeum (L.) C.Presl

Rhizome creeping or ascending, short, bearing approximate fronds seemingly in a crown. Fronds dimorphic, young fronds densely covered with long, lax hairs, glabrescent and nearly naked when mature; stipe short, enlarged and winged at base, fleshy when young; sterile fronds pale yellowish green, pinnate-pinnatifid, ovate-lanceolate, 30-80(-100) × 15-25 cm, soft papery, gradually narrowed toward acuminate apex; pinnae sessile, more than 20 pairs, 5-20 × 1.5-3 cm, incised ca. 2/3 toward costa, apex acuminate; ultimate lobes entire, margin with hairs often mixed with black ones, apex rounded; lateral veins forked; fertile fronds usually shorter and developing earlier than sterile fronds, 2-pinnate; pinnae sessile, 2-4 × ca. 1.5 cm, incised almost to costa; ultimate segments 2-4 mm wide, covered throughout with sporangia. 2n = 44.

Sandy or alluvial soils in swamps low woods and thickets. Moist areas, acidic soils, frequently in vernal seep; at elevations up to 2,300 metres. Often in dense populations in marshy places in mountainous areas.