Late leaf peeping this year? Experts weigh in on why we might be seeing some delays in fall colors in Colorado high country
There are some yellow aspens and leaves on the ground up in Summit County, but locals are wondering why there aren't more right now as we head into late September and the majority of deciduous trees still hold green leaves.
While temperature is a part of the equation, sunlight is really the main drive for trees to start the change; when nights get longer, trees get the picture and can sense the change in seasons and prepare for colder, darker days.
Still, we aren't seeing more night than usual this time of year, so why are the leaves staying?
Mountain Newsroom Reporter Spencer Wilson spoke with two professors with CU who explained, yes, that extra moisture this year for our trees could be the reason why they seem to be changing slower.
"It could be the case," Stephanie Mayer, associate professor at CU's Department of Ecology and Evolutionary Biology, said. "Anything that's a stressor like dry, excessive dryness or excessive heat can cause that color change to happen earlier."
Barbara Demming-Adams, CU professor in ecology and evolutionary biology, explained our trees are basically getting mixed signals.
On one hand, it's getting colder and nights are getting longer, but if moisture is still pretty present, the tree believes there's still growing to be done this season and therefore needs its leaves to photosynthesize. But if the tree waits too long to change colors and drop its leaves it can be dangerous and detrimental to the plants.
Leaves create a wider surface for snow to weigh down branches and potentially break them, plus if the leaves don't change color, the tree misses out on recycling nutrients for next season.
"The green is valuable, that has nitrogen," Demming-Adams said. "That's a limiting thing for plants. The yellow and the red is just carbon...we don't need to take all of this down and store it in our safe, they do that with the nitrogen. They want every nitrogen atom for next year."
When the tree pulls the nitrogen back in, it removes the green color from the leaves, leaving whatever pigments are still there; your reds, yellows, oranges, and sometimes purples.
For best color shows, our experts said the climate will play a big part, so long as there's no surprise early winter storms to ruin the fun.
"The best shows typically happen when you have warmer days and cooler nights," Mayers said. "So if you have, you know, if we get a sudden cold snap, as we often do, like really cold snap below freezing, then that's probably going to put the kibosh on a lot of the beautiful colors that we normally see."
CBS News Colorado will continue to update the latest color forecasts for different areas as the colors progress.
