Think you’re seeing fall colors already in Colorado? 

Maybe think again. 

“It’s not really fall colors,” said Dan West, the entomologist and longtime leaf watcher with the Colorado State Forest Service who thinks he’s seen what you’ve seen. 

“You can’t really always tell the difference between fall colors and drought-stressed trees,” he explained. “It’s no different if you didn’t water your house plants for a couple of months. You’re gonna be like, ‘Wow, that plant looks yellow.'” 

West has seen that yellowing on cottonwoods and willows. And what’s happening to them, he said, is also happening to Colorado’s most celebrated tree of fall: aspen. 

Following a historically dry winter and spring in the mountains and a hot, dry start to summer in parts of the state, “it’s really just water-stressed trees that are shutting down the process early,” West said. 

By that, he means the process that turns foliage from green to yellow. With enough water, trees might keep producing chlorophyll and maintain their greenery. Without enough water, they might stop production and shed the greenery, revealing the golden hues adored come September before the leaves drop. 

Also without enough water, those yellowing leaves might appear brown on the edges, West noted. 

“It just kind of looks dull and not as vibrant,” he said. “I would anticipate that going into this fall, but it’s too hard to tell right now.” 

Toward the end of July, 9NEWS senior meteorologist Chris Bianchi pointed to “a pretty good run” of monsoonal rains in the mountains. 

“If that continues ー that’s a big if ー if that continues through August and early September, we may get a glimmer of good news and perhaps a better season,” he said. 

For the time being, he predicted peak colors appearing “a little bit earlier because of that drought stress.” 

As did West ー “maybe a week or so early, certainly a few days earlier,” he said. Typically, colors peak first around mid-September in the state’s northern mountains, followed by the central mountains, then the southern ranges in early October. 

Rain or lack thereof in the coming weeks indeed matters, West said. “If we can continue to get a little bit of sporadic moisture, it will leave those leaves on a little bit longer and perhaps buy us a little bit more time to pull off a show.” 

But the show depends on several factors other than moisture. 

Warm, sunny days and cool nights lead to the most vibrant leaves. A freeze leads them to shrivel and drop early. Wind poses another risk, along with insects and disease. 

West looks out for signs of infestation and infection around this time every year during research flights over groves. Pests and fungi are more prevalent in wet years, “which is why the past couple of years we haven’t seen a lot of maladies on aspen statewide,” West said. “It’s really pockety in nature.” 

He also tracks growth, which appears to be stunted amid drought, he said. That means fewer leaves, “which typically translates into not as great of a show in the fall.”

But “a lot can change between now and then,” he emphasized. “Hang on, let’s see how it goes, and let’s all do our rain dances.”