- Advertisement -

Drought causes leaves to turn brown and wither before reaching their peak color. Heat waves cause leaves to fall before autumn. Extreme weather events such as storms that completely strip trees of their leaves.


For a joyous autumn activity, leaf peeping is facing some serious threats from the era of climate change.

- Advertisement -

Leaf-peeping, the practice of traveling to see nature display its fall colors, is a beloved annual activity in many corners of the country, particularly in New England and New York. But recent weather has been disrupted by weather conditions there and elsewhere, and that trend is likely to continue as the planet warms, arborists, conservationists and ecologists said.

related: Report says climate change could force more than 200 million people to relocate by 2050

Leaves cascade into warmer colors across the US, usually by the end of September. This year, many regions have not yet pivoted from their summer green hues. In northern Maine, where extreme conditions typically occur in late September, forest rangers reported less than 70% of color change and moderate leaf drop on Wednesday.

Across the country in Denver, higher temperatures have left “dead, dry edges of leaves” early in the season, said Michael Sundberg, a certified arborist in the region.

“Instead of trees making this gradual change, they throw off these frustrating weather events. They change abruptly, or they drop leaves early,” Sundberg said. “It’s been a few years since we’ve had a really good leaf year where you just drive around town and see really nice colors.”

The reason climate change may be worsened by autumn has something to do with plant biology. When autumn arrives, and day length and temperature drop, the chlorophyll in a leaf is broken down, and this causes it to lose its green color. Green gives way to yellows, reds and oranges that make for dramatic autumn displays.

People enjoy the view of autumn at Kurugol Nature Park in Deuz, Turkey on November 29, 2020. (Photo via Getty Images by Omer Urr/Anadolu Agency)

Achieving those extreme colors is a delicate balance, and jeopardized by changes in the environment, said Paul Schaberg, a research plant physiologist with the U.S. Forest Service based in Burlington, Vermont. Warmer fall temperatures can cause leaves to remain green for a longer period of time and the peeping colors of leaves can delay the onset of fall color, he said.

Worse, dry summers can stress trees and cause their leaves to miss fall color altogether, Schaberg said. A 2003 study in the journal Tree Physiology noted that “environmental stresses may accelerate” leaf decline, said Schaberg Cowrote.

“If climate change means significant drought, it means trees are going to shut down, and many trees are just about to drop their leaves,” he said. “Severe drought which really means the tree can’t function – it doesn’t improve color.”

This is already happening. Heat this summer in the Pacific Northwest brought temperatures over 110 degrees Fahrenheit (43 Celsius) in Oregon, and caused a condition called “foliage scorch,” in which prematurely brown leaves, Chris Still, forest ecosystems and said a professor. Society Department at Oregon State University.

The pigment of the leaves had deteriorated and they fell off shortly thereafter, however. This will lead to a less beautiful fall season in parts of Oregon.

“It’s just a really great example of a color change due to heatwave shock,” Still said.

related: More than 200 medical journals warn that climate change is the ‘greatest threat to global health’

Climate change also poses long-term threats that can disrupt leaf peeping. Andrew Richardson, professor of ecosystem science at Northern Arizona University, said the spread of diseases and invasive pests and the northward creep of tree species are all factors tied to warmer temperatures that can create less vibrant fall colors.

Yankee magazine foliage expert Jim Salge said the onset of fall colors, which tend to drift later in the fall, may continue later.

“The last decade has been more years in my observations than what we would later consider historical averages,” he said.

The economic impact of bad leaf-peeping seasons can also be consequential. Officials across New England have said that fall tourism brings in billions of dollars to those states each year.

Conservationists say this is a good reason to focus on conserving forests and reducing burning fossil fuels. Andy Finton, landscape conservation director and forest ecologist at The Nature Conservancy, said recent fall seasons in Massachusetts have been less spectacular than usual, but if forests are given the protection they need, leaf peeping could be a part of the state’s heritage. may be a part.

“If we can keep large, important forests intact, they will provide us with what we depend on – clean air, clean water, clean forests, as well as the motivation to fall,” Finton said.