This vegetation type is dominated by tall herb Asclepias syriaca, a neophyte of North American origin, which was planted as an ornamental or textile plant in the past. It now occurs along roads and railways, at the edges of vineyards, in disturbed places in human settlements and along river banks. Soils are often dry, ranging from loamy to stony. In the Czech Republic this vegetation occurs in warm lowland to colline areas; available phytosociological relevés are mainly from southern Moravia.