Male fern is a very long spore plant of the family Polypodiaceae. The rootstock is flat, 25 cm long, thick, black-brown outside, with many thin roots. From the forefoot young part of the leaves go out of the leaves, and the back old part gradually disappears. No overhead stem. The leaves are up to 1 m long, with up to 30 cm long handles, covered with numerous thin, testicles and brown flakes. At the top the leaves are dark green.

In Bulgaria  the male fern is found in wet and shady forest places in the bushes, mainly in our bigger mountains up to 1800 m above sea level.

Rhizoma filcis-maris of the male fern is used. Picking is in August - October and March - April, with rhizomes being dug in autumn or early spring, shaking violently from the soil and cleaning well from the roots.

Male fern is used as a raw material for the chemical-pharmaceutical industry for the manufacture of pharmaceuticals as well as in veterinary medicine.