The individualistic concept of vegetation is based on three principles: (1) vegetation continuum, (2) ecological and chorological individuality of species and (3) multidimensional variability of vegetation. All principles reflect phenomena existing in nature. The conclusions arising from these principles are these: (1) plant communities (phytocoenoses) are not natural objects (wholes) as such but merely mixtures of plant individuals coexisting on the same site as the result of migration and environmental selection, (2) the classification of vegetation is quite arbitrary if not pseudoscientific, and (3) vegetation phenomena can be reduced to phenomena of plant individuals.
The integrated concept of vegetation considers the phytocoenoses as real functional systems (wholes) where plant populations are integrated both by the environment and by interactions among and within plant populations. The principles of the individualistic concept, but not the above conclusions arising from them, are compatible with the integrated concept. Phytocoenoses limit the individualistic performance of species through restriction of ecological amplitudes and shifting of ecological optima (as compared with physiological amplitudes and optima). The individualistic behaviour of species does not exclude the formation of coenological groups of species which form a basis for the classification of vegetation according to floristic-coenological criteria. Under natural conditions, plant communities are usually interconnected by transition zones to form a vegetation continuum. Phenomena of the vegetation continuum do not cause greater difficulties in syntaxonomy than those of polymorphic taxonomic groups in plant taxonomy.