Economic Importance

Pteridophytes have several practical uses: Rumohra adiantiformis (leather-leaf fern) is grown for cut-flower arrangements; Marsilea is eaten as food; Azolla is used as a biofertiliser (thanks to its symbiotic nitrogen-fixing cyanobacterium); Dryopteris filix-mas has traditionally treated tapeworm infection; Pteris vittata can remove heavy metals from contaminated soil (bioremediation); Pteridium species yield a green dye from their leaves; Equisetum stems, being gritty with silica, were traditionally used for scouring; and several genera — Psilotum, Lycopodium, Selaginella, Angiopteris, Marattia — are popular ornamentals. …