Some trees in Maine are already losing their leaves, weeks ahead of peak fall foliage season.
Jay Wason, a professor of forest ecosystem physiology at University of Maine said abnormally dry weather is stressing some vulnerable trees.
"All that means is that the trees have detected that 'hey, conditions are not great for me any more to maintain these expensive leaves to do photosynthesis, so I can ditch them now and go into my winter dormant mode,'" Wason said.
Drought conditions developed in Maine over the summer and most of the state was still in a moderate drought as of last week.
Wason said trees exposed to heat and dryness are more likely to lose their leaves early.
Trees that are "up on a ridge top, someplace that is a little more likely to have drier conditions develop more quickly than like a valley location where there might be more reliable water in a relatively dry period," he said.
Species such as aspen and birch are more susceptible to drought effects, Wason added.
Despite the ongoing drought, the Maine Department of Agriculture Conservation and Forestry said a mix of sunny days and cool nights the state has experienced is an ideal mix for producing strong leaf colors.
The department monitors foliage progression across the state every fall and its first report is due on Sept. 10.
"Overall, the 2025 foliage season is still expected to be terrific, with brilliant reds, oranges and golds that draw visitors every year," said department spokesperson Jim Britt.
