The Rocky Mountains belt in the Northern American continent can offer very specific life conditions to plants. Mountain species make up about 75% of the total plant species number of this region, in the sub-Alpine zone they are even more numerous. The range of climatic conditions in the Rocky Mountains is so great that it permits the growth of a large number of species, of which vascular plants are estimated exceed 900. Each of the altitudinal zones has its typical dominant association.
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© P. Kovář