Whitebark pine (Pinus albicaulis) forests are declining across most of their range in North America because of the combined effects of mountain pine beetle (Dendroctonus ponderosae) outbreaks, fire exclusion policies, and the exotic pathogen Cronartium ribicola, which infects five-needle white pines and causes the disease white pine blister rust. Predicted changes in climate may exacerbate whitebark pine decline by (1) accelerating succession to more shade tolerant conifers, (2) creating environments that are unsuitable for the species, (3) increasing the frequency and severity of mountain pine beetle outbreaks and wildland fire events, and (4) facilitating the spread of blister rust. Yet, whitebark pine tolerates a variety of stressful conditions and the broad genetic diversity to adapt to changes in climate and disturbance. To learn more about this see the Science Spotlight Restoring whitebark pine ecosystems in the face of climate change.
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