Polystichum acrostichoides (Christmas fern) is an evergreen fern native to eastern North America from Nova Scotia west to Minnesota and south to Florida and eastern Texas. Its common name, Christmas fern, derives from its evergreen nature, with fronds growing to 30-80 cm long and 5-12 cm broad, pinnate with 20-35 pair of pinnules. The spores are produced on small pinnules toward the apex of the frond. It greatly resembles the Pacific Coast sword fern, Polystichum munitum, but does not make the huge clumps of that fern, and differs from it in the constriction of the fertile pinnules. Like other ferns of the genus Polystichum, it is allied to the wood ferns, genus Dryopteris, which it often is found growing close to.