Big Picture: Sierra Nevada Epidemic

Rising temperatures and invasive pathogens are threatening Sierra Nevada forests, which provide critical ecosystem benefits for California, including water and carbon cycling. Environmental science, policy, and management PhD candidate Joan Dudney is collaborating with government agencies—including the U.S. Geological Survey, the National Park Service, and the U.S. Forest Service—to investigate the impacts of mountain pine beetles and white pine blister rust on five pine species. Working in the lab of Professor John Battles, Dudney uses surveys, computer modeling, leaf-isotope analyses, and dendrochronology to identify which trees are most vulnerable to climate change. Preliminary data indicates that the sugar pine is declining in two national parks, but no blister rust was found on foxtail pines (pictured here). The foxtail pine is among the world’s longest-living pine tree species.