Allen County, OH (WLIO) - A late September walk at Teddy Bear Park in Lima reveals a few hints of fall color breaking through the green leaves. We look forward to the changing leaves every year, but why do the leaves turn? There's actually a fascinating science behind it all.
"Our deciduous trees, those big, flat leaves can't survive the wintertime so some of the evergreens do hold on to their leaves all winter long but those deciduous trees got to give it up when it gets too cold, when it starts to freeze," says Johnny Appleseed Metropolitan Park District Naturalist Dan Hodges.
Just like we eat food for nutrients that keep us alive, trees use the sun's energy through a process called photosynthesis which creates sugars that feed the plants.
The leaves actually reveal their true colors during the autumn season because all summer, they have been covered by this green mask. It's a pigment called chlorophyll which is produced by the long daylight hours. We lose daylight significantly heading into fall and this chlorophyll production diminishes. That allows us to see the true colors of the reds, oranges, and yellows.
Weather plays a role in when that peak occurs and for how long. An ample supply of sunshine in the late summer and early fall paired with those cool, but not freezing nights is the key to get those brilliant displays.
"With warm sun and if it's not frozen it hasn't damaged the leaf. The leaf is going to keep making those sugars. If you get enough of those kind of hanging around the tree starts to produce these red colors as well," adds Naturalist Dan Hodges.
Good news for those looking to do some leaf peeping this fall. The Ohio Department of Natural Resources says the state is primed for a brilliant display of colors, of course, all contingent upon the weather.
"The fact that, unlike last year, we're already starting to see those changes now. We would expect that is definitely a good sign that this is going to be a good year for fall colors," says Ohio Department of Natural Resources Fall Color Forester David Parrott.
The big question - when will the fall foliage peak? ODNR tells us they are predicting the colors to peak in the northern tip of the state around October 17th, central Ohio around October 24th, and southern Ohio as we head closer to Halloween. For Lima, we are estimated to peak in the October 17th to 24th range. You can keep track of the changes from north to south with ODNR's fall color progress map here.
