When Dan West heard on the radio last week that the fall foliage color change had started already in Summit County, he reacted with skepticism and a bit of annoyance.
It’s not that he doesn’t appreciate the beauty of a hillside embroidered with yellow and gold aspen stands in September. It’s just that the entomologist for the Colorado State Forest Service was dubious that the change had begun so early.
“I thought, ‘Here we go again,’” West said. “We need to stop with the misinformation and just give people the facts.”
West, who annually spends late summer inspecting forests in the state from an airplane to determine their health, drove to Summit and Eagle counties last weekend to see for himself. His suspicions were confirmed.
“There is a little bit of yellowing, but itap a stress response to drought stress,” West said. “There is some of what is called marginal necrosis, leaf burning around the edges, which is an indication that it just doesn’t have enough water. When itap losing more water than it’s gaining, it starts to die off the edges of the leaf. Ultimately, a portion of the leaf near that brown area goes yellow first. Then it just goes brown.
“Around that brown edge is this little line of yellow,” West added. “From afar, it makes the tree look almost like itap yellow, but itap not. Itap more brown than it is yellow.”
West believes the fall color change will begin in two to three weeks in the northern mountains, slightly earlier than normal, followed by the central mountains along the Interstate 70 corridor a week later. Last year, the peak began about the third week of September.
Many aspen still look green and appear to be fine, West said, but he observed stressed aspen at Breckenridge, Frisco, Silverthorne, Vail Pass and Vail.
“Itap pretty widespread along the I-70 corridor,” West said. “I think itap a pretty safe bet to say reports of early fall colors are really more of a report of poor aspen condition and stress from trees with not enough water. Walking through the forest, I was kind of amazed at how thin some of the aspens already look. Most of that is because they get this drought stress, so they start to shut down their processes a little bit earlier.
“I think thatap whatap happening,” he continued. “There are already brown leaves that are falling off trees as we speak.”
That doesn’t mean fall colors will be a bust when the actual fall color change comes in September, West said.
“I still think there is going to be a show,” West said. “On the west side of Vail Pass, those stands look as green as green can be. Sometimes thatap one of the prettiest spots (for fall foliage) in all of Colorado. There are many, many trees that still look green, that look fine.
“I think a month from now, we’re going to see some stands that might go a little bit earlier (than normal) in color. Some stands will be more muted. And I think we’re not going to see as many of the deep oranges and dark reds,” he added.
