Floristic composition of vegetation in habitats suitable for Erigeron × huelsenii (Asteraceae)

The paper provides data on the fl oristic composition of vegetation in anthropogenic habitats suitable for Erigeron × huelsenii, a spontaneous hybrid between the alien E. canadensis and native E. acris s. str. The study is based on 21 phytosociological relevés (vegetation plots) of 5×5 m size made in 2013–2014 in the Polish part of the Lithuanian Lakeland (north-eastern Poland) using the Braun-Blanquet method. The plots were taken on a roadside verge, a roadside slope, in abandoned sand and gravel pits, and on arable fi elds with grass-legume mixtures. There are 91 species of vascular plants, four species of bryophytes, three species of lichens, and one species of cyanobacteria. Vegetation is represented by populations of species typical of plant communities from the classes Stellarietea mediae, Artemisietea vulgaris, Koelerio-Corynephoretea, FestucoBrometea and Molinio-Arrhenatheretea. Two fl oristic groups recognized from hierarchical cluster analysis and principal component analysis correspond with ruderal and segetal habitats. The study reveals that arable fi elds with grass-legume mixtures on sandy soils can be very suitable for E. × huelsenii.