Autumn has moved souls since the beginning of time.
“Delicious autumn! My very soul is wedded to it, and if I were a bird I would fly about the earth seeking the successive autumns.” — George Eliot
It is the most romantic of seasons, which explains why so many people outside of Door County wonder, often aloud to someone in Door County via telephone or email, “When do the leaves turn color?”
The short answer is: “In the fall.”
The long answer?
Well, according to the United States National Arboretum (USNA), “To understand the whole process, it is important to understand the growth cycle of deciduous trees and shrubs.”
If you have the time, you can read all about it (usna.usda.gov/PhotoGallery/FallFoliage/ScienceFallColor.html), but, as you might be able to tell from the above sentence, it might be easier if you let me try to whittle the process down.
Cooler temperatures are just one of the environmental factors that lead to what the USNA poetically describes as “painting deciduous woodlands in glorious fall colors.”
As the nights grow longer, the corky layer of cells at the juncture of the leaf and stem grow thicker and block the flow of carbohydrates and minerals from the roots to the leaves, which causes the production of chlorophyll to slow and then stop.
Chlorophyll is what makes leaves in spring and summer appear green, by masking the yellow and orange pigments that become apparent to our eyes in the fall.
Meanwhile, that stem/leaf connection grows corkier, until, finally, the leaf falls off, hence the other name for the season.
Temperature, amount of sunlight (versus cloudy days), and soil moisture help to determine the quality of fall colors.
But let’s return to the arboretum website for the final description of what makes for good fall colors: “A growing season with ample moisture that is followed by a rather dry, cool, sunny autumn that is marked by warm days and cool but frostless nights provides the best weather conditions for development of the brightest fall colors. Lack of wind and rain in the autumn prolongs the display; wind or heavy rain may cause the leaves to be lost before they develop their full color potential.”
Sure, that explains the colors of autumn, but what about the electricity in the air and the sense that even though winter is coming, life is grand?
Or, at least, that’s my intimate relationship with autumn. It’s always been more about high promise than imminent decline.
But let us not argue about autumn. Instead, let’s go out on a high note with a standard from the American songbook:
The falling leaves
Drift by the window
The autumn leaves
Of red and gold
I see your lips
The summer kisses
The sunburned hands
I used to hold
Since you went away
The days grow long
And soon I’ll hear
Old winter’s song
But I miss you most of all
When autumn leaves
Start to fall