White pine blister rust has been spreading through western forests since 1910, causing widespread mortality in a group that includes some of the oldest and highest-elevation pines in the United States. The disease has recently reached Colorado and is expected to travel through the southern Rockies. Although it cannot be contained, RMRS researchers and collaborators are developing proactive strategies that integrate conservation, ecology, and genetics to prepare ecosystems for invasion of the pathogen.
Genetic resistance occurs in a small percentage of individuals in each of the five-needle pine species that are susceptible to the rust. Researchers and managers are identifying how common this resistance is in forest stands and where resistance is located on the landscape by collecting seeds and screening seedlings exposed to the rust for signs of disease development. This information is integrated with new ecological research on population dynamics, climate interactions, and conservation activities to develop management strategies, which may include planting of resistant seedlings or creating regeneration opportunities near resistant trees. Rocky Mountain National Park, which was hit by the rust in 2010, will be one of the first adopters of the proactive management strategy to protect their limber pine populations. Managers with the U.S. Forest Service, other National Parks, and Canadian land management agencies are also putting the proactive approach into practice.