Skip to main content
U.S. flag

An official website of the United States government

Increased whitebark pine (Pinus albicaulis) growth and defense under a warmer and regionally drier climate

March 2, 2023

Introduction: Tree defense characteristics play a crucial role in modulating conifer bark beetle interactions, and there is a growing body of literature investigating factors mediating tree growth and resin-based defenses in conifers. A subset of studies have looked at relationships between tree growth, resin duct morphology and climate; however, these studies are almost exclusively from lower-elevation, moisture-limited systems. The relationship between resin ducts and climate in higher-elevation, energy-limited ecosystems is currently poorly understood.

Methods: In this study, we: (1) evaluated the relationship between biological trends in tree growth, resin duct anatomy, and climatic variability and (2) determined if tree growth and resin duct morphology of whitebark pine, a high-elevation conifer of management concern, is constrained by climate and/or regional drought conditions.

Results: We found that high-elevation whitebark pine trees growing in an energy-limited system experienced increased growth and defense under warmer and regionally drier conditions, with climate variables explaining a substantive proportion of variation (∼20–31%) in tree diameter growth and resin duct anatomy.

Discussion: Our results suggest that whitebark pine growth and defense was historically limited by short growing seasons in high-elevation environments; however, this relationship may change in the future with prolonged warming conditions.

Publication Year 2023
Title Increased whitebark pine (Pinus albicaulis) growth and defense under a warmer and regionally drier climate
DOI 10.3389/ffgc.2023.1089138
Authors Nicholas E. Kichas, Gregory T. Pederson, Sharon M. Hood, Richard G. Everett, David B. McWethy
Publication Type Article
Publication Subtype Journal Article
Series Title Frontiers in Forests and Global Change
Index ID 70242788
Record Source USGS Publications Warehouse
USGS Organization Northern Rocky Mountain Science Center