Biochemical Diversity of Ponderosa Pine and Predation by Bark Beetles (Coleoptera: Scolytidae)

To determine if mountain pine beetle, Dendroctonus ponderosae Hopkins, influences patterns of biochemical diversity in ponderosa pine, Pinus ponderosa Laws., monoterpene composition of xylem resin of trees that survived an infestation was compared with a random sample of living trees adjacent to the infestation. No significant differences were detected in means or variances between the two groups of trees. A comparison of these populations to populations of ponderosa pine with a history of western pine beetle, D. brevicomis LeConte, infestation revealed large differences in biochemical diversity between the two geographic areas. Association of geographic differences in biochemical diversity with insect species exhibiting different feeding habits suggests possible causal relationships between these two patterns.