Xerothermic grasslands on the chalky slopes deviding arable fields near Zamość (South Poland) were subject in 2OO4-2OO5 to phytosocioligal investigation with the Braun-Blanquet method. The study area is dominated by the Inuletum ensifoliae association of the Festuco-Brometea class. Two variants of the association were distinguished (l) the initial one, developed on the fields abandoned long time ago, with weak presence of Inula ensifolia and more abundand Linum flavum, and (2) the typical one, well established, floristically richer, with abundand Inula ensifolia. Three other associations representing Trifolio-Geranietea sanguinei, with Trifolium rubens, Vincetoxicum hirundinaria and Peucedanum cervaria, as well as one of Rhamno-Prunetea, with Cerasus fruticosa, occurred on a very small part of the area in patches under 25 m². Cessation of extensive grazing and mowing several years ago has caused expansion of trees and shrubs of Rhamno-Prunetea class a major threat to the studied xerothermic communities. In addition they are being enriched in nutrients leached-out and running down the slope from the arable fields in the upper range.

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