Autumn has fallen
By CHRIS ESSIG
of The (Galesburg) Register-Mail
GALESBURG — Today officially kicks off the fall season.
Known as the autumnal equinox, the event occurs when the sun is directly above the Earth’s equator, causing an equal amount of time during the day and night.
“It’s a specific moment in time,” said Chuck Schulz, professor of physics at Knox College.
That moment will be 10:09 p.m. CST. In the Northern Hemisphere, that means the birth of the fall season, while Southern Hemisphere citizens will celebrate their spring season.
For Knox County residents, fall begins today, but the first full day of fall is Thursday. For residents in different time zones, the first day of fall may land on a different day.
Beyond the astronomical implications, equinoxes also are historically significant. Ancient cultures, for instance, used the famous Stonehenge pattern in England to recognize equinoxes. Pagans also celebrate the two equinoxes — fall and spring.
But for many Americans, the equinox is a simple reminder of the brisk, winter months ahead.
“Folks start getting their snow shovels ready,” Schulz said.
Soon the days will be getting shorter, causing temperatures to drop. Tree leaves across the area will turn shades of vibrant red, yellow and purple before shedding in preparation for the end-of-the-year chill.
In the summer, the colors of tree leaves are masked by overwhelming green. When temperatures dip and the amount of daily sunlight drops as winter nears, less green pigment, called chlorophyll, is produced in the plants, causing the shades of red, yellow and purple to shine through.
Tim Tibbetts, professor of biology at Monmouth College, said the change in color is the plant’s response to the change in seasons.
The process already has begun, said Jan King, owner of Walnut Grove Farm near Knoxville, noting maple trees she has seen that already are showing some color.
“It seems a little early,” she said. “Every year is a little different.”
Likewise, farmers recognize the autumnal equinox as a largely symbolic day, instead of an absolute measure of the beginning of fall, said Kyle Cecil, an agriculture expert with the University Illinois Extension in Knox County.
This year’s early harvest is a prime example that fall, in many ways, is well under way.
“In the broad sense, fall has begun with the harvest,” he said.