An Overview of the Origins of the Modern Vegetation and Flora of the Northern Rocky Mountains

The present flora of the northern Rocky Mountains has diverse origins.The Late Cretaceous mesothermal to megathermal evergreen vegetation of this region had few taxa, even at the familial level, that live in the northern Ro ok i i leaved deciduous taxa occupyi they un nderwent major diversification.Bes early Eocene thermal maximum severely restricted the areas of l lineages By the early middle Eocene, volcanic sehen that supported micrathera coniferous forests of Pinaceae and Cupressaceae had developed in s of the northern Rocky Mountain region.These ades into newly created T climate.During Eocene by way of Beringia.Some of the Eocene microthermal lineages s in the northern Rocky Mountains today, and other extant lineages, although ultimately derived from taxa in the Eocene uplands, represent morphological types S -ated and diverged in Eurasia, arriving in North America by migration.Oligocene and Neo northern Rocky Mountains, although the Columbia Plateaus [s oe t contain m of these ages.Th l broad-lea .deciduous or coniferous forests, t lineages that were derived fro the terminal Eocene temperature deterioration.With the presence of many extant northern Rocky Wolfe, Jack A. 1987."An Overview of the Origins of the Modern Vegetation and Flora of the Northern Rocky Mountains."Annals of the Missouri Botanical