Weather in the coming weeks could change or break Vermont’s fall foliage
This month, Michael Snyder, Commissioner of Vermont Forests, Parks and Recreation, is keeping a close eye on the weather.
With most of Vermont classified as unusually dry by the US Drought Monitor — and much of southern Vermont even drier — what happens over the next few weeks will likely determine how impressive this year’s foliage will be.
Snyder is hoping for one of two scenarios: If the hot weather continues into the fall, he expects the colors of the leaves to gradually change, slowly evolving into a fall palette.
Even better, he said, would be if Vermont experiences cold nights and bright sunny days with some showers. In that case, Snyder predicts that by the end of September, the forest will be popping up in particularly bright colors — “kind of crazy colors that you’re not supposed to see in nature,” he said.
But if the unusually dry parts of Vermont deteriorate into extreme drought, the much-anticipated shift from green to red, yellow and orange will accelerate. Leaves turn brown faster – the worst case.
The effect is more than aesthetic. The fall season in Vermont is a booming tourism industry that attracts over a million visitors and about $300 million in visitor spending during the fall foliage season, according to Heather Pelham, commissioner for the Vermont Department of Tourism and Marketing.
Given the weather so far this year, much of the state could be hitting the fall color Goldilocks zone: spot on.
That’s because some of the extra pigments created as trees prepare for the colder months, like the leaves’ red color, are actually protective compounds, said Joshua Halman, the forest health program manager in the Vermont Department of Forests, Parks & recreation Production is stimulated during times of stress, which includes the colder weather that is part of the seasonal change.
If dry conditions are minimal enough and cause just enough extra stress on the tree, the drought can increase production of these protective compounds, allowing this year’s leaves to show up with even more color.
In southern Vermont, which is currently rated as moderately to severely dry, Halman expects there will be more muted leaves that fall earlier in the season. However, he said there is a chance this will improve in wetter weather.
Another component that could be impacting fall foliage this year is the spongy moth caterpillar, which Halman said was most active in the Champlain Valley and parts of the Connecticut River Valley. Early in the season, tree leaves were being removed by the moth larvae, causing additional stress on the trees.
“In some areas of the state — the west side of the state, particularly where there has been severe spongy moth defoliation for a few years in a row — I think we can expect some trees to not have good colors and some trees to have muted colors,” Snyder said.
However, the foliage will grow back, but the leaves are currently smaller and less vividly green than healthier trees.
“[Trees]aren’t good at increasing stress, so if you have one year after year and then another and another, the trees start to give up,” Snyder said.
Don’t miss anything. Sign up here to receive VTDigger’s weekly energy and environment email.