Autumn is my favorite time of the year. The ambient temperature is comfortable for working outdoors, the gardening chores are winding down for the year, and of course, here in Ohio the leaves change colors. Colorful autumn foliage is Mother Nature’s artistic finale before the dreary gray days of winter dominate the landscape.
When Do Leaves Change Color in Northern Ohio
Decreasing daylight hours and weather patterns are the major influences for when leaves change color. Shortening daylight hours signals trees that the growing season is coming to an end. To prepare for winter, deciduous trees shed their leaves.
This process begins when the cells at the base of each leaf stem begin to divide rapidly and shut off the food supply pathway. This, in turn, causes the green pigment in chlorophyll to fade. Other pigments, which have been masked all summer long by this more intense green pigment, now become visible and give us brilliant yellow and orange fall foliage colors.
Here in Northern Ohio, colorful autumn foliage reaches its peak in mid to late October. But weather determines the intensity of fall foliage colors as well as the duration of the season. I can remember a year when my neighbor’s sugar maple tree began changing colors in early September. Why so early, you ask?
What Causes Leaves to Change Color
The yellow and orange pigments in colorful autumn foliage is species-specific. For example, the leaves on the silver maple in my backyard fade to an unimpressive yellow in fall. My neighbor’s sugar maple produces a much bolder orange color. But sugar maples are one of the species of trees which can also produce red fall foliage colors.
Unlike the yellow and orange pigments, red pigment is not present in sugar maple leaves during the summer. This pigment is produced in response to weather conditions. Warm August days and cool nights create the most intense red fall foliage colors. Other species of trees noted for their ability to produce red fall pigment include dogwoods, Washington hawthorn and red oak.
Thus, when I see stems of leaves turning red at the very top of my neighbor’s sugar maple, I know we have a chance for a beautiful fall foliage show. I say a “chance” because a windy or stormy day in October can blow that colorful autumn foliage off the trees prematurely.
When that happens, I know it’s time to pick up the rake and begin fall cleanup. It’s not the funnest job in the world, but hey, at least leaves make a good addition to the compost pile!
