Mountain pine beetle and Great Basin bristlecone pine: A complicated story

Abstract

During the 1990s through 2010 bark beetle-caused tree mortality was a hot news topic in the western United States (US). An estimated > 5 Mha were affected by multiple bark beetle species. A large proportion of the total tree mortality, however, was attributable to a single species, the mountain pine beetle (MPB, Dendroctonus ponderosae Coleoptera: Curculionidae, Scolytinae). MPB has a large current distribution (Baja California Norte through the western United States and into British Columbia and Alberta, Canada), is polyphagous on most Pinus species within its range, and true to its name has adapted to mountain climates. Recorded hosts to MPB include multiple five-needle high-elevation pines (Pinus albicaulis, P. aristata, P. fl exilis, P. strobiformis, P. balfouriana), and most other pines when they are growing at moderate to high elevations in the western US (P. contorta ssp. murrayana and latifolia, P. edulis, P. lambertiana, P. monophylla, P. monticola, P. ponderosa) (Furniss and Carolin 1977, Wood, 1982). Notably missing from this list is the iconic Great Basin (GB) bristlecone pine (P. longaeva). Does this suggest that GB bristlecone pine is not a suitable host to MPB? If yes, are both MPB oviposition preference and larval performance deterred in GB bristlecone pine? Conversely, if GB bristlecone pine is a suitable MPB host, why are infestations rare and undocumented? I provide an overview of the current knowledge of the intriguing relationship between MPB and GB bristlecone pine.

Citation

Bentz, Barbara J. 2019. Mountain pine beetle and Great Basin bristlecone pine: A complicated story. Mountain Views. 13(2): 28-32.