Colorado fall colors 2024: Leaf-peeping could be spectacular

Start marking your calendars now, fans of fall foliage, because it looks like spectacular leaf-peeping is in store for Colorado this year.

That’s the outlook according to Dan West, one of the state’s leading forestry experts, who spends a lot of his time in airplanes every August, evaluating forest health across the state.

“From the air, everything is looking very green,” said West, an entomologist for the Colorado State Forest Service and a member of the faculty at Colorado State University. “I was down in Durango last week, looking at the southwest corner and man, they are green. Fields are green, as opposed to tan, as they were a year ago. Everything looks really nice down there.

“Same for the central part of the state,” he continued. “The whole Gunnison Basin has been above-average in precipitation — they’ve been getting the afternoon monsoonal flow — so things look like we’re setting up for a really good season.”

The onset of fall colors is primarily triggered by shorter days and longer nights, but environmental factors do play a role, resulting in variations from season to season.

West is predicting a normal season this year, which would mean seeing the first signs of color change — “a tinge of yellow,” as he put it — around Sept. 9 in the northern regions of the state. As such, the peak there would occur somewhere between Sept. 16-27.

West predicts the peak coming to the Interstate 70 corridor the last week of September.

Healthy forests make for awesome leaf-peeping. And, when it comes to aspen trees specifically, West said they seem to be doing great with few exceptions.

“I mapped almost no disturbance in aspen stands,” West said. “When I say disturbance, I’m talking about insects and disease. Some years we have environmental conditions that are perfect for fungal issues on leaves. We didn’t have that develop this year. That’s usually (caused by) a wet spring, followed by a really warm trend. We didn’t see that this year, so we didn’t end up with foliar issues — the fungi that feed on the foliage of aspens. We mapped almost no foliar issues in aspen.

“There are very small, isolated pockets of defoliating insects,” he added, “but nothing that’s widespread, nothing like what we’ve seen in years past, where the whole Grand Mesa was affected. It just hasn’t happened this year. It’s setting up to be a really good season.”