With fall continuing and winter on the way, many have noticed the changing colors of leaves.

Iowa Department of Natural Resources Interpretive Naturalist and Educator Anne Riordan says that when leaves first return after winter, they are green, which is because of the chlorophylls that help plants make sugars for food. She tells Raccoon Valley Radio that the green pigment is more noticeable because there is more of it, but that other colors begin to show when those chlorophylls die off in colder weather.

“The yellows and the oranges, the carotenoids are the pigments that become visible. But then also as we have some of the warmer days that we’ve had and cooler nights, there are some pigments that are actually formed during those times because sugars are produced during those warmer days, but then they’re kind of trapped in the leaves. And so that causes anthocyanins to be formed, which are pigments that are red and purple.”

Riordan mentions that these new pigments coming forward are what creates the beautiful fall scenery many are accustomed to seeing this time of year.