Populations of whitebark pine (Pinus albicaulis) are declining throughout most of the species range because of high levels of mortality from the exotic fungal pathogen (Cronartium ribicola) that causes the disease white pine blister rust in five-needle pines, and periodic upsurges of the endemic mountain pine beetle (Dendroctonus ponderosae). The absence of fire in some forests has also led to advanced succession of shade-tolerant species and subsequent reductions in whitebark pine. Finally, increased atmospheric warming and associated effects from altered precipitation patterns further threaten to reduce the geographic distribution of the species.

Precipitous declines in whitebark pine have cascading effects throughout the ecosystem primarily because of the subalpine and treeline positions the species occupies. When forest stands succumb to mortality, few if any other species exist to fill the structural and functional roles of whitebark pine. Notably, whitebark pine presence dampens snow melt, stabilizes soils, provides cover and birthing habitat, and its seeds are highly nutritious and consumed by a wide array of vertebrate species.

For over thirty years researchers and managers have sought to understand whitebark pine ecology, and to devise and implement procedures to reduce population decline and restore these valuable high-elevation ecosystems. The documents presented in this Hot Topic are a collection of the key contributions from this effort.

This hot topic was developed in partnership with the Fire Effects Information System.