Bracken or Common bracken (Pteridium aquilinum) is a perennial herb, from the group of fern species. Ferns are one of the oldest representatives of higher plants which formed roots for the first time in the plant world. The underground stem of the bracken is modified in to rhizome. In a cross-section of it in its thickest part, there is a dark spot resembling the silhouette of two-headed eagle, hence the name of the plant in Bulgarian Orlova paprat (en: Eagle's fern). Its rhizome can reach several meters in length and is highly branched, as in spring time a single leaf would grown from every branch. Bracken leaves reach a height most commonly between 0.5 to 1.5 m and sometimes up to 2 or 3 m. The petiole is long as the lamina or longer. Double to triple petiole of each plant leaf, whose main parts are also standing on their own stems, create the illusion of triple leaf also called frond.
On the frond's underside the bracken bears sporangia, gathered in groups. They are protected by the curled frond edges. This feature is so characteristic for the bracken, that it alone is sufficient to determine the species and distinguish it from all other ferns occurring in Bulgaria. After the sporangia ripped, the sori contained in them are dispersed by wind and germinate, forming new germs. After the formation of root, stalk and leaf the embryo begins its independent life and turns in to an older plant. Except the spores Bracken can also reproduce vegetative by dividing the rhizome. Rhizome snippets above 5 cm can be planted successfully.
All parts of the plant are poisonous. Poisoning occurs when parts of the plant (especially rhizome) have been consumed as food. In Central Europe there are reports on poisoning by domestic animals, if the content of bracken in the hay is over 20%.
Bracken can have many different applications. The folk medicine uses rhizome and leaves collected in summer. The roots are rich in starch and they can be used for the production of glue, beer and rough flour for animal feed. The plant also contains sparkling substances, which could be used for laundry and washing instead soap.
The Common Bracken is а heliotrope species spread almost all over the globe. It grows throughout temperate moist, grassy areas, scrub spots in the forest outskirts and diluted forest glades, steep slopes up to 1800 m asl. It often forms large grasslands alone or rarely with bindweed and other species typical for in-durmast hornbeam, beech woods and partly in the coniferous belt in place of destroyed forests. It prefers sandy soils on silicate basis.
The species is found under the appropriate conditions scattered in all regions of the country, but most stocks are in the mountainous regions, mainly in the beech and coniferous belt of the Balkan, Sredna gora, Pirin, the Rhodopes, Vitosha, where it forms pure communities.