Pteridium Aquilinum

Pteridium aquilinum, commonly called bracken, brake, pasture brake, or eagle fern, is a fern native to Eurasia and North America that now has a cosmopolitan distribution across temperate and subtropical regions of both hemispheres, in the family Dennstaedtiaceae. A herbaceous perennial growing 0.3 to 1 meter tall from an underground rhizome, it produces large, roughly triangular fronds, dies back each season, and forms dense colonies of genetically identical fronds that can persist for more than 1,400 years; it thrives in acidic soils across pastures, woodlands, and hillsides from southern Alaska to northern Mexico and the Greater Antilles. It contains the carcinogenic compound ptaquiloside, linked to haemorrhagic disease in livestock and gastric cancer in humans, yet is the fifth most widely distributed weed in the world and is eaten in Korea and Japan despite the toxicity risk.