ABSTRACT
Population is the set of individuals of one species within which there is relatively free gene flow. As a result, all individuals in a population are genetically similar. Plant ecologists define plant population the set of individuals of the species in the phytocoenosis. This population was named coenopopulation. A more reasonable viewpoint regards coenopopulation as a part of population. J. Grinnell described the ecological niche of California tracher. He characterized its food and foraging method, place of sheltering and nesting, and its relation to climatic factors and to plant communities. When all factors important to an organism are included in an ecological niche, many believe ecological niche and ecological range are synonyms. Sufficiency of pollination is in the forefront among the factors of reproduction control in many cases. The main mechanisms of coenotic regulation of reproduction are linked with the level of diffusive competition in phytocoenosis and neighbourhood of individuals entering a reproductive cycle.
