Ecological Investigations of Thlaspi Alpestre L. Along an Elevational Gradient in the Central Rocky Mountains

Plants of Thlaspi alpestre L. (Cruciferae) from a high elevation population in the Medicine Bow Range of Wyoming were genetically dwarfed. These plants broke dormancy and entered dormancy more rapidly than a subalpine population from the same area. The overwintering of seed of T. alpestre before germination in the field may be caused by properties of the seed coat. The distribution of T. alpestre at high elevations is limited in part by a low reproductive ability; at low elevations, competition and infection by pathogens may shorten the life span of T. alpestre and limit its distribution.