Mature and old growth forests are dominated by large, old trees, which disproportionately influence forest structure and contribute greatly to ecosystem services relative to their abundance. These large trees provide important wildlife habitat and forage, affect local temperature and moisture conditions, store significant amounts of carbon, and influence local nutrient cycling and availability. Large trees accumulate slowly in forests and the death of a single tree can have widespread effects on the surrounding ecosystem. Recent research has indicated that large trees may have elevated sensitivity to climate change, putting the future of these arboreal giants in question.

In this project, Ella will explore past recruitment — the process of existing trees growing to a size threshold that is considered large — and survival dynamics of large trees at Mount Rainier National Park. Working with park scientists and managers, she will use existing, long-term data to track changes in large tree abundance at Mount Rainier; identify environmental factors correlated with large tree mortality; and forecast how climate change may affect mortality risk for large trees within and around the park. She will synthesize the results of her analysis to create risk metrics for individual species and risk maps covering the park for managers to incorporate into their decision-making processes.

Ella and her collaborators hope the results of this work will help answer questions about which species may be more susceptible to climatic changes; where in the park large tree abundance may change the most; and where managers can best focus their efforts to protect these ecologically and culturally important trees.