EN
One of the many areas where Matteucia struthiopteris (L.) Tod. is found in Poland is the upper part of the Vistula River Valley, mainly in the Silesian Foothills and the Silesian Beskid. From 2005 to 2010, floristic and phytosociological studies were carried out to determine the presence of ostrich fern stands and plant communities that contain this species. As a result of this study, 31 sites on which the species was found were identified. With the help of phytosociological relevés collected using the Braun-Blanquets method, six plant associations were identified that are subject to different levels of anthropopressure. The most commonly observed form the degeneration of plant communities containing the species is neophytisation. In all of the phytocoenoses studied, from two to nine kenophytes were identified. Of these, Impatiens glandulifera, Reynoutria japonica and Robinia pseudoacacia play a significant role in shaping phytocoenoses and pose a threat to the Matteucia struthioptheris population. In order to protect sites on which Matteucia struthiopteris grows, it is necessary to mechanically combat invasive plant species and extend legal protection to the best preserved phytocoenoses which contain the species.