The anthropogenic prairie flora and vegetation that replaces the original forests of the surroundings of Temuco (Cautín, Chile) were studied. It was worked with a table made with 220 vegetation samples obtained with the phytosociological European methods. The flora is formed by 187 species of perennial, annual and biannual weeds, of the Classes Dico - and Monocotyledons, of those a 42% corresponds to autochthonous species, upon considering the abundance, this percentage is reduced to 27%. The most important species of the flora are: Agrostis capillaris, Leontodon saxatilis, Juncus procerus, Mentha pulegium and Anthoxanthum utriculatum. They were determined 10 plant associations: Mentho-Agrostidetum capillariae, Juncetum procerii, JuncoAgrostidetum capillariae, Anthoxanthetum utriculatae, Agrosto-Lolietum perennis, Bromo-Poetum annuae, Hyperico-Agrostidetum capillariae, Cynosuro-Agrostidetum capillariae, Airo-Agrostidetum capillariae and Cynosuro -Piptachaetetum montevidensis, belonging to the Agrostidion chilense. It is made a comparison of the attributes of the flora of each association. To a summarized table of l O associations with the cover average of the species was applied statistic multivariate analysis of classification and ordination. It is concluded that in the study region could have existed indigenous prairie and that the anthropogenic prairie vegetation current is more diversified than the original forest vegetation, but both present a similar altitudinal distribution pattern.