In the paper a state of preservation and the characteristics of flora of the cultivated fields of the Kaluszyńska Upland is given. The flora of agrocenosis of the Kaluszyńska Upland is rich. The presence of 278 vascular plant species was noted in the study area. It is mainly the diversity of habitats and human activity that affected its species abundance. More than a half of a number of taxa (166 species - 59,6%) belong to the group of rare, 40 of them are endangered extinction. Among the most threatened species there are 14 taxa e.g.: Fumaria schleichen, Euphorbia exigua, Illecebrum verticillatwn, Aspe- rugo procumbens, Polycnemum arvense, Radiola linoides, Camelina sativa.
A phytosociological classifi cation and the characteristics of weed communities developing in root crops of the Kałuszyńska Upland are given in this paper. The presence of three associations: Digitarietum ischaemi, Echinochloo-Setarietum and Lamio-Veronicetum politae, as well as of two communities: Setaria pumila–Setaria viridis and Panico-Setarion alliance, has been found. The differentiation in trophic and soil moisture conditions of habitats results in the fl oristic diversity of communities, divided into lower phytosociological units. Two variants have been distinguished within the association Digitarietum ischaemi, whereas Echinochloo-Setarietum has been divided into 2 subassociations and 6 variants.