Researchers investigate how drought stress, competition, and forest conditions may affect white oak survival.
A University of Kentucky researcher is using expertise gained from years of studying tropical rainforests to investigate a growing concern affecting Appalachian forests: the decline of young white oak trees.
Sybil Gotsch, an associate professor of forest ecophysiology in the Department of Forestry and Natural Resources within the Martin-Gatton College of Agriculture, Food and Environment, is examining what forestry experts call the “white oak problem.”
Although mature white oak trees remain widespread and new seedlings continue to emerge, relatively few are successfully progressing into the sapling and mid-aged stages needed to sustain future forests.
The issue has attracted attention from ecologists, foresters, wildlife managers, and industries that rely heavily on white oak. “The stakes go well beyond the forest,” said Gotsch.
“White oak acorns are a food source for deer and turkey, and the trunks provide roosts for bats. The wood is also essential for furniture, flooring and cabinetry.”
White oak also plays a vital role in Kentucky’s bourbon industry because federal law requires bourbon to be aged in new charred white oak barrels.
According to a 2021 assessment by the White Oak Initiative, many mature forests lack enough young trees to replace aging populations.
Gotsch, along with colleagues John Lhotka and Lance Vickers, is investigating why many young oaks fail to advance beyond key stages of development.
“There are several possibilities. One is drought stress. Young oaks stuck beneath the shade of taller trees may not be getting enough water or light to push through to the canopy, especially during dry summers,” Gotsch said.
“Another possibility is what scientists call an allocation problem — the tree might be putting its energy into roots or defenses instead of growing taller. Then there is a third factor, which could be competition.”
Using canopy research methods refined in Costa Rica and Mexico, Gotsch is collecting data high above Kentucky forests. “It feels like this secret world that I have the great honor to be able to study,” Gotsch said.
“You think it works a certain way, and then you get up there and realize you were completely wrong. That's what I love about this work — it never stops raising new questions.”
Photo Credit: gettyimages-paul-hartley