ABSTRACT
The distribution of the vegetation in the alpine and timberline ecotone of southwest Alberta is quantified for six specific locations along a 600-km section of the Rocky Mountains. Both G. W. Argus and D. J. White and J. Gould have produced lists of the rare vascular plants of Alberta, and their distribution in the alpine zone is similar. The rare taxa occur mainly in the transition zone at Plateau Mountain and Waterton National Park. However, the numbers are increasing as botanists discover the rarity of many of the species. The Late Wisconsin ice sheets largely destroyed the pre-existing vegetation in southwest Alberta except for species that survived on nunataks, e.g. Plateau Mountain. These may have permitted the survival of a few local endemics within the arctic/alpine vegetation at a few isolated locations in the middle section of the Rocky Mountains, which appear as the Middle Cordilleran endemic flora.
