Abstract
Two ruderal seam communities, the Lactuco-Anthriscetum caucalidis and Ahthrisco-Asperugetum procumbentis, are described in Slovakia. Both communities occur on loess in regions of warm and dry climate. Besides the species of the Galio-Alliarietalia, those of the Sisymbrietalia and Artemisietalia design the floristical composition of the communities. Numerical classification and ordination techniques were adopted to clarify systematic relations of the communities and show the structure of the revealed clusters. A comparison of the results of the numerical methods and the syntaxonomical table synthesis has been performed and briefly discussed.
