Dryopteris cristata

Dryopteris cristata is a perennial species of fern native to wetlands throughout the Northern Hemisphere. It is known as crested wood fern, crested buckler-fern or crested shieldfern. This plant is a tetraploid species of hybrid origin, one parent being Dryopteris ludoviciana and the other being the unknown, apparently extinct species, dubbed Dryopteris semicristata, which is also one of the presumed parents of Dryopteris carthusiana. D. cristata in turn is one of the parents of Dryopteris clintoniana, another fern of hybrid origin. The crested wood fern is a wetland 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. This plant is toxic....read more on Wikipedia.