Avena strigosa Schreb. in agrocoenoses of the Podlaski Przełom Bugu mesoregion

The research on the localities of Avena strigosa and on its increased occurrence in agricultural crops of the Podlaski Przełom Bugu was carried out in 1994-1998. The documentation of this research consists of 600 phytosociological relevés and the floristic records. The paper presents the composition and structure of the field plant communities where Avena strigosa was found. It occurs frequently on various soil types of the Podlaski Przełom Bugu. However, on the area examined it was found just in small numbers, covering up to 5% of the area, while in the eastern part of the area an increase in its occurrence was observed. In the area of the Podlaski Przełom Bugu Avena strigosa occurred in spring cereals in the communities of Arnoserido-Scleranthetum and Vicietum tetraspermae as well as in the poor field communities, with the character species of Aperion spicae-venti and Panico-Setarion. Additionally, Avena strigosa was also found in the field communities of root crops belonging to Panico-Setarion alliance; however, it was present there just in small numbers