Pteridium Gleditsch ex Scopoli. Subfamily: Hypolepidoideae. Bracken.
A genus of 2-11 species, cosmopolitan in distribution. Bracken taxonomy remains provisional; the molecular work of Der et al. (2009) and Zhou et al. (2014) outlines a probable taxonomic structure for the genus, though rank decisions will remain controversial. It is my perception that all evidence supports the recognition of three taxa in eastern North America, at specific rank. Pteridium is a notorious and nearly worldwide weed (though less consequential in our area than in many parts of the world), nearly impossible to eradicate because of its deeply subterranean rhizomes. Bracken fiddleheads are sometimes eaten, but they are poisonous and highly carcinogenic. Bracken is not favored by grazing animals, and increases its abundance under grazing pressure. In overgrazed pastures, however, cattle will graze on bracken, the carcinogenic compound (shikimic acid) then transmittable to humans through milk.
Ref: Christenhusz, Fay, & Byng (2018); Der et al. (2009); Jacobs & Peck (1993) In Flora of North America Editorial Committee (1993b); Liao, Ding, Wu, & Prado in FoC (2013); Speer & Hilu (1998); Speer, Werth, & Hilu (1998); Thomson (2000); Thomson (2004); Thomson, Mickel, & Mehltreter (2008); Tryon (1941); Zhou et al. (2014). Show full citations.