Chemosystematic Studies in the Genus Abies. Iv. Introgression in Abies Lasiocarpa and Abies Bifolia

Summary The volatile oils of the leaves of alpine fir were analyzed by gas‐liquid chromatography. In the Pacific Northwest, alpine fir separates into two types, Coastal and Rocky Mountain. They were distinguished by quantitative differences in santene, tricyclene, camphene, β‐pinene, myrcene, β‐phellandrene, borneol, and ∗∗∗bornyl acetate. Coastal populations had red colors in the periderm, whereas the Rocky Mountain populations had only brown colors. A literature search revealed additional differences between these populations which were originally described as Abies lasiocarpa (Hook.) Nutt. and A. bifolia Murray, respectively, and more recently as only A. lasiocarpa or as a single variety of A. balsamea. However, our evidence suggests that the original designations more accurately describe these two populations, which have hybridized extensively.