Whitebark pines (Pinus albicaulis) are picturesque, long-lived, and hardy trees that thrive at sites with harsh climates, where few or no other trees survive. Whitebark pine is the dominant timberline tree in subalpine habitats at Crater Lake and Lassen Volcanic National Parks. Their large and nutritious seeds are prized by wildlife including Clark's Nutcrackers, black bears, and ground squirrels. Other wildlife use trees for shelter. Whitebark pine canopies support lichens and other plants. These trees also stabilize soil and regulate snowmelt.
White pine blister rust is a fungal infection caused by the non-native pathogen, Cronartium ribicola; this fungus is killing significant numbers of whitebark pine. Changes resulting from the disease are likely to have profound, ecosystem-wide effects. We monitor the pathogen and its impact on white bark pine.
Since 2012, we have monitored whitebark pine at Crater Lake and Lassen Volcanic National Parks to determine the current status of this species and long term trends.
Objectives are to:
- Infection and death rates of whitebark pine from blister rust disease, mountain pine beetle, and other agents (fire, native diseases) over time.
- Associated plant species composition
Evidence of infection from blister rust and mountain pine beetles
Tree and seedling characteristics