Experimentally evaluating effects of postfire drought on establishment, growth and survival of two widespread western conifer species; lodgepole pine and Douglas-fir (greenhouse portion of experiment)

This research seeks to understand how drought following wildfires
affects the establishment of two widespread Rocky Mountain tree
species, lodgepole pine and Douglas-fir. In Yellowstone National Park,
warming, drying conditions are leading to increased frequency of
severe wildfires that kill existing trees and trigger regeneration of
the forest. These trends are expected to continue. Many tree species
in Yellowstone are well adapted to fire. Yet, early and abundant
seedling establishment after fire is critical for forests to recover.
Tree seedlings are particularly sensitive to drought, and evidence
suggests that sufficiently dry postfire conditions could cause
widespread tree-seedling mortality, with ecological consequences that
may last decades. This research will determine how seedlings from two
tree species respond to drought conditions expected in the mid-21st
century and will identify the physiological mechanisms that drive
seedling response to dry conditions. The results of this study will
advance understanding of how forests in the western United States will
respond to environmental change over coming decades and provide useful
information for western land managers who are grappling with increased
wildfires.