These low-growing, open annual grasslands, dominated by Heleochloa schoenoides, are typical of exposed lake bottoms with saline soils. The soils contain a large proportion of clay. They are wet in spring but dry out in summer. Occasionally stands of Heleochloa schoenoides occur in vernally flooded depressions on arable fields. Currently this vegetation is only found at two sites in southern Moravia, although in the past it was probably more common in that part of the country.