The first burst of fall air is a reminder of the changing of the seasons, and soon, a colorful landscape across the region. The Iowa Department of Natural Resources has released its first weekly Fall Color report for the entire state. In South Central Iowa, the DNR reports a bit of color is starting to show, especially along field and woodland edges. The white ash and green ash are turning purple and yellow respectively, sumac and ivy are starting to get red, and bottomland species are turning yellow including walnut and cottonwood.

Professor of Biology at Central College Paul Weihe says there are two primary drivers in how leaves turn from green to various colors.

“One of those would be sort of the yellows, oranges, and golds, and those really are pigments that were present in the plant all along, but those were masked by the green, and that’s what most of us were taught about how color change works,” he says. “But there’s the whole category of colors which are the reds, purples, and some of those really vibrant ones–those are actually produced in response to the changing conditions as we enter the autumn, so those are really acting as a sunscreen to protect the tissues within the leaf, while the tree is recovering some of those materials that the leaf is made out of for recycling and use the following year.”

According to the Iowa DNR, the peak season is expected to be between October 15th and 20th locally.