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Illinois


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Illinois - Fall Color Report Iowa - Fall Color Report Minnesota - Fall Color Report Wisconsin - Fall Color Report
Illinois - Fall Colors      
       


Missouri


 

Kentucky

Indiana Michigan
Missouri - Fall Color Report Kentucky - Fall Color Report Indiana - Fall Color Report Michigan - Fall Color Report
       


Additional information:

Cool Autumn Weather Reveals Nature's True Hues

Fall Colors across the United States - US Forest Service

Why Leaves Change Colors - US Forest Service
 


Many people think that cold weather is solely responsible for the color change in leaves, but not so. Leaves begin to turn before we have any frosts. Change in coloring is the result of chemical processes, which take place in the tree as the seasons change.

During the spring and summer, a food-making process takes place in the leaves, within cells containing the pigment chlorophyll. This gives the leaf its green color. The chlorophyll absorbs energy from sunlight, and uses it in transforming carbon dioxide and water to carbohydrates, such as sugars and starch.

In the fall, the decrease in intensity and duration of sunlight, and the cooler temperatures, cause the leaves to stop their food-making process. The chlorophyll breaks down, the green color disappears, and the yellowish colors or other pigments already in the leaf become visible. 

Autumn weather conditions favoring the most brilliant colors are warm sunny days and cool, but not freezing, nights. A few hard frosts can cause the leaves to wither and fall from the tree without changing color. The degree of color may also vary from tree to tree. Leaves directly exposed to the sun may turn red, while those on the shady side may be yellow. When warm, cloudy and rainy weather dominates the fall season, leaves tend to have less coloration.

Some trees across central Illinois begin to change colors during late September.  Fall colors usually peak from mid October into early November across central and southeast Illinois.