Vascular floras of 43 forest associations and variants are revealed on the basis of a set of 537 releves made in Kivach nature reserve (middle taiga subzone; Karelia, Russia). For each of the floras, spectra of fractions of both latitudinal and general species distribution are calculated. Proportions of different fractions are seemingly characteristic either of particular classes of habitats (like slope bottoms, river valleys, or rock outcrops of different chemistry), or of forest types and groups of ecologically similar types following V.N. Sukachev's approach. As a result of synthesis of data on plant chorology and the Holocene spore/pollen spectra checked for the study area, the system of Holocene plant migration types which reflects the main stages of post-glacial forest flora formation is proposed. The Praeboreal "nucleus" is revealed and the proportions of the both Boreal and Atlantic migrants are pronounced in the floras of all the syntaxa. But only the flora of Piceeta oxalidosa, restricted to brook valleys, is dominated by the Atlantic element and hence displays the south-boreal features. The most of the coniferous forest syntaxa floras seem to have finished their genesis by the beginning of the Subboreal. Floras of basiphilous pine forests represent continental features due to their enrichment in the Subboreal element, whereas the proportion of species acting as man's followers in the Subatlanticum is higher in mesic small-leaved forests.