Editor’s note: This story has been updated to correct Wilfred Previant's current title.
Continued, abnormal heat in the Pikes Peak region could affect the color-changing cycles for aspen trees in the area.
High temperatures and drought have likely stressed trees, but cooler temperatures in the near future could be the impetus for color change, said Wilfred Previant, an assistant professor at Colorado State University and former manager of the Forest Inventory, Analysis, and Monitoring Program with the Colorado State Forest Service.
When overnight lows dip below 40 degrees, aspens take it as a cue to shed their green-inducing chlorophyll and change from green to gold, Previant said. Cooler temperatures “really trigger the tree to start sending those sugars down to its roots so it can get ready for the next spring,” he said.
The good news for leaf-peepers is sub-40 degree lows could be on the way in the area, according to National Weather Service meteorologist Eric Petersen. Though Colorado Springs won't see temperatures in the 30s in the near future, Woodland Park and Monument are both expected to experience temperatures under 40 degrees early next week after a cold front rolls in late Monday night, Petersen said. The rest of September, however, will continue to be abnormally warm, he said.
The key will be if a couple of cool nights in a row will be enough to cue the aspens to change color. Previant is optimistic there are still golden hues to be found in the state. “My assumption is leaves should be turning, and this should be a great weekend,” Previant said.
To make it a truly great weekend, Previant is headed to the mountains surrounding Nederland, which has an elevation 8,230 feet and is about 15 miles west of Boulder.
Areas like Nederland are good places to look for aspens, he said, because the higher elevation and northern location make cooler temperatures more common. And avalanche shoots are a great place to look.
But much of the tree-peeping game could be changing because of climate change, Previant said. Variable precipitation patterns and hotter temperatures would place trees under stress. “If the trees are stressed, they typically won't change colors," he said. "They’ll just go to brown or dull yellow.”
Harsh conditions are currently the reality for the northwest corner of the state, much of which is experiencing extreme drought, and some of which is undergoing exceptional drought, the highest level of classification, according to the U.S. drought monitor.
Colorado Springs is not facing a drought right now, according to the monitor, but that doesn't mean the changing climate won't play a role soon, Previant said.
"Whether you're in an urban center or city park, there's legitimate concern about what the drought means and longtime patterns," he said.