What better way to begin an overview of the splendors of autumn than with … well, an overview of the vast now no-longer verdant vegetation of the vales and vistas of Vermont?
NOTE: The Drone Video Is Best Viewed FULL SCREEN
Remind Me Again Why the Leaves Change Color
Most of us have a vague recollection of learning why leaves change color in the fall from our school days. But let’s do a quick recap.
To begin with, Jack Frost can stop taking all his bows, because it’s not his handiwork.
Trees, like the rest of, like to eat. But unlike you or me, they are able to manufacture their own food. This process takes place in the leaves in cells filled with chlorophyll via photosynthesis.
Chlorophyll is the green pigment that we all associate with leaf color. It plays a crucial role in using the energy from the sun to convert the water from the tree’s roots and carbon dioxide [CO2] from the air into sugars and starches that feed the tree, and as a by-product gives off oxygen [O2].
But sitting right along with chlorophyll in the leaves’ cells are several other chemicals, including carotene and xanthophyll which you see in the orange color in carrots and yellow in corn. They’ve been there all summer working just as hard as the green chlorophyll.
But in autumn when the days get shorter and the temperatures cool off, the production of chlorophyll begins to slow down, then breaks down and disappears. So now it’s the time for the oranges and yellows of carotene and xanthophyll to be noticed and take center stage. They were there the whole time – just masked by the green chlorophyll.
But some colors – viz., the reds and purples particularly associated with maples and sumacs – have NOT been hidden all summer long. They’re being made de novo. The sugars made late in summer or early fall, particularly with warm, sunny days, are chemically converted at that time of year to anthocyanins.
And the fact that the reds and purples of anthocyanins require bright sunshine is the reason that some trees are two-toned, with leaves at the top and outside a gorgeous red or purple, while inner and lower leaves deprived of all that sunshine display the more common yellows and oranges.
At the very end, I’ll post some solid Links with information used in putting this together that have more details, along with maps showing locations near you to enjoy Autumn’s Kaleidoscopic Color Show.
But let’s enjoy some of my favorite photos of the fantasia of fall …
RESOURCES
http://extension.illinois.edu/fallcolor/updates.cfm
http://extension.illinois.edu/fallcolor/education.cfm
http://www.foliagenetwork.com/
http://www.weather.com/maps/fall-foliage