He has worked at Free Air CO2 Exchange (FACE) sites in forest and desert environments around the world. He operates a precipitation manipulation experiment in the desert at Big Bend National Park in Texas and is a close collaborator with the USDA working on water stress response in crops including peanut.
In addition, he was a founding member of PrecipNet, an international consortium of scientists studying the impact of variable rainfall on native and agricultural ecosystems.
His goal is to determine the mechanisms that regulate and integrate the developmental and physiological processes that influence leaf level carbon balance and plant growth from the cell to the ecosystem level. This information will determine the impact of climate factors on carbon and water flux and ultimately, on growth and in natural and agricultural ecosystems.