We are combining field and laboratory studies to determine how hydraulic traits of evergreen leaves affect their tolerance of temperature extremes with change in atmospheric CO₂ concentrations.

There is an urgent need to understand how climate warming and associated increase in atmospheric CO₂ concentrations will affect evergreen vegetation in temperate climates. This multidisciplinary project spans biophysics to evolutionary ecology to investigate how hydraulic traits of temperate evergreen leaves affect their tolerance of seasonal variation in low and high temperature extremes with change in atmospheric CO₂ concentrations. Emphasis is given to understanding how small diameter xylem conduits enhance frost tolerance and their hydraulic implications for the morphology and function of leaves that might constrain carbon gain under warmer temperatures, particularly in association with greater evaporative demand.