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Population dynamics are deeply correlated with the life histories of the orchid species via their reproductive strategies,reproductive success in certain habitats,longevity of rhizomes or other perennial structures,and condition of their mycorrhizal symbionts.Majority of plants have ability to both sexual and asexual reproduction however the latter is often overlooked in the research on the reproductive strategies of particular species and reproductive success of their populations.Wetland orchids demonstrate higher intensity of vegetative (asexual)reproduction (VR) than drier habitats specialists.That could be evolutionary stimulated by two non-related reasons: a lack of pollinators and a sufficient amount of resources to maintain an additional growth.The intensity of VR is specific for orchid growth habits (Tatarenko,1996) and can be climate-dependent (Tatarenko et al.,2004).The VR demonstrates very stable annual rate which means lower annual population dynamics in species having it as a predominant way of reproduction.Few dramatic changes in plant numbers in populations of Pogonia japonica,Epipactis thunbergii noted during our studies were due to some bacterial or fungal diseases spreading easily along the roots and rhizomes connecting ramets.Species with significant predominance of VR are Pogonia japonica,Hammarbya paludosa,Epipactis thunbergii,E.palustris,Eleorchis palustris,Dactylorhiza iberica.