By Emma Cotton/VTDigger
Vermont forests have experienced floodwaters, a general excess of moisture, wildfire smoke, unexpected frost and heat waves this growing season. Still, according to state officials, none of those conditions are expected to disrupt the fall foliage season.
“In general, things look really good,” said Josh Halman, forest health program manager for the Vermont Dept. of Forest, Parks and Recreation.
On the heels of receding floodwaters that proved disastrous for many business owners, Vermonters are looking to the trees with their fingers crossed, hoping for a spectacle of red and gold that will bring tourists and confirm that much of Vermont is, indeed, open for business.
In some parts of the state, maple trees have already turned red — a potential symptom of all the moisture, Halman said, but not an entirely unusual phenomenon for late summer.
“It’s not crazy to see a few trees this time of year that have turned red in different locations. But with all this rain, I think people are picking up on it a little more than usual,” he said.
Halman surveys the forests from an airplane each year with his colleagues, and this year’s survey took place last Tuesday, Sept. 5. Halman said some areas of the Northeast Kingdom are already showing vibrant colors, and generally, forests look healthy.
Still, moisture can impact the colors of the leaves in several ways, Halman said. The first is that too much water can stress trees.
When Vermonters watch trees change color, they’re watching the trees reabsorb nutrients and carbohydrates that the leaves have created in the summer, which the trees transfer back to their stems and roots.
“It’s a way of saving all that stuff that they worked so hard for during the growing season,” Halman said. “And when that happens, they’re reducing the chlorophyll contents in the leaves. And that’s why the yellows and oranges are observed at that point.”
If trees are waterlogged, the trees become stressed and need the nutrients sooner, which could cause leaves to change color earlier in the season.
Moisture can also make leaves more susceptible to fungal diseases, which Halman said are not currently widespread but have impacted some of the state’s maples. Leaf fungi could have an impact on fall foliage colors.
In an annual fall foliage forecast for New England Magazine, Jim Salge, a former meteorologist at Mount Washington Observatory in New Hampshire, predicts that leaf fungi are the “biggest concern, and biggest question mark, about the season.”
Both Halman and Salge expect some of the trees to turn early. But Salge predicts that El Niño conditions may cause warmer temperatures during late summer and fall, which could cause the colors to last longer and peak later, producing a longer foliage season. He also predicts more pastel colors and fewer reds due to the warm, wet weather and the moisture.
“They’d still be beautiful, just less bold,” Salge wrote in his forecast.
Halman said the biggest indicators of the foliage season remain to be seen. A recipe of cool, crisp nights and warm, sunny days typically produce the most vibrant colors.
“For those trees that don’t have those fungal pathogens, the color really is going to be driven by what’s happening between now and peak color,” he said. “So if we have those cool nights and those sunny days, those trees are gonna look fantastic.”
