Title: Identifying Candidate Genes Associated with Cold Adaptation in Douglas-fir

In forest trees from temperate and boreal regions, cold acclimation is an important adaptive trait that involves changes in gene expression and physiology. Genecological, quantitative genetic, and QTL studies have been used to study the genetics of cold acclimation in Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco), but the genes responsible for variation among individuals and populations remain unknown. Douglas-fir seedlings from a low elevation, coastal Oregon population and a high elevation, inland Washington population were grown in a common garden in Corvallis, Oregon, and artificial freeze tests were used to compare their cold hardiness from September, 2004 to May, 2005. Cold hardiness was associated with the timing of bud set and bud flush, and there were large population differences in cold acclimation, deacclimation, and bud phenology. In late October, for example, population differences in percent cold damage (predicted at-7°C) were as large a