Healthy forests in the western United States provide multiple benefits to society, including harvestable timber, soil stabilization, and habitat for wildlife. On the Navajo Nation, over 5 million acres of forest provide wood that heats 50% of homes, building materials, summer forage for livestock, and drinking water. However, warming temperatures and changes in precipitation patterns can increase forests’ vulnerability to insect outbreaks and catastrophic wildfire. Forest managers, particularly those associated with tribal communities that depend on forests to maintain a subsistence lifestyle, need knowledge-based tools in order to reduce the impacts of climate change on forests.
This project aims to study approximately 700,000 acres of ponderosa pine and mixed-conifer forests within the Navajo Nation to understand how tree growth is influenced by the interaction between climate variables, such as temperature and precipitation, and the quantity and quality of trees found in western forests. Researchers will work closely with the Navajo Forestry Department to build on their existing forest inventory database and collect tree-ring data that can be used to estimate tree growth during periods of low and high-water availability and under different forest stand densities. The results of this project will help to inform the development of a new Forest Management Plan for the Navajo Nation. In particular, analysis of these tree-ring data will answer the question of how and why drought stress varies across the forests of the Navajo Nation, information which can be then used to inform forest management aimed at increasing forest resistance and resilience to drought, for example, by thinning forest stands.
