Dryopteris cristata A. Gray is a species of fern

Fern

A fern is any one of a group of about 12,000 species of plants belonging to the botanical group known as Pteridophyta. Unlike mosses, they have xylem and phloem . They have stems, leaves, and roots like other vascular plants...

 native to wetlands throughout the Holarctic Kingdom. It is known as the crested wood fern. This plant is a tetraploid species of hybrid origin, one parent being Dryopteris ludoviciana

Dryopteris ludoviciana

Dryopteris ludoviciana, the Southern Wood Fern, is fern native to southern United States from Florida west to Texas and as far north as Kentucky and North Carolina....

and the other being the unknown, apparently extinct species, dubbed Dryopteris semicristata, which is also one of the presumed parents of Dryopteris carthusiana

Dryopteris carthusiana

Dryopteris carthusiana H.P. Fuchs is a species of fern native to damp forests throughout the Holarctic Kingdom...

. D. cristata in turn is one of the parents of Dryopteris clintoniana

Dryopteris clintoniana

Dryopteris clintoniana, commonly known as Clinton's wood fern, is a fern of hybrid origin native to the northern hemisphere. It is a fertile hexaploid, arising as a species by doubling of its chromosome number from a hybrid between Dryopteris cristata, a tetraploid, and Dryopteris goldiana, a...

, another fern of hybrid origin.

The crested wood fern is a wetland

Wetland

A wetland is an area of land whose soil is saturated with water either permanently or seasonally. Wetlands are categorised by their characteristic vegetation, which is adapted to these unique soil conditions....

s plant, needing year-round moisture. The fronds often grow quite tall, up to a meter or more in height, but are extremely narrow under most conditions.

Anti-microbial properties

It is known that this plant has been used as an anti-microbial agent; for example, root extracts from D. cristata (as well as the kindred species D. arguta

Dryopteris arguta

Dryopteris arguta, with the common name coastal woodfern, is a species of wood fern. It is native to the west coast of North America, where it grows in oak woodlands and shady low elevation slopes in Southern California and north.-Description:...

) has been shown efficacious in expelling intestinal parasites from certain mammal

Mammal

Mammals are members of a class of air-breathing vertebrate animals characterised by the possession of endothermy, hair, three middle ear bones, and mammary glands functional in mothers with young...

s.