God's Crayon Box

The whole concept of autumn- with it's chilly temperatures, frost, brilliantly-colored trees and the aroma of fireplace smoke- is quite intriguing to me, probably because for most of my life it has meant little more than a subtle shift from "scorching hot" to "cool but nice." This year, for the first time in many years, I have watched autumn unfold almost before my eyes. I have worn a jacket in SEPTEMBER! I have watched my frosty breath as I exhale in October. And now, as I walk through our neighborhood in November, I smell the wood burning in the fireplaces and watch the trees change color almost daily.

What makes some trees' leaves turn yellow and/or orange while others turn bright red and purple? Small amounts of yellow and orange pigment are in the leaves all along- we just can't see it during summer when there is so much green chlorophyll, which aids in the process of photosynthesis (turning water and carbon dioxide into oxygen and glucose), in the leaves . During the autumn season, trees begin to go dormant in preparation for winter with its decreased water and sunlight (also necessary for photosynthesis). The green chlorophyll disappears from the leaves leaving behind the yellow and orange pigments. And we see orange and yellow leaves. In some trees, like maples, glucose is trapped in the leaves after photosynthesis stops. Sunlight during the day and cool temperatures at night cause this glucose to turn red- and we see red and sometimes purple leaves. Other trees, like oaks, leave wastes in the leaves- and we see brown leaves.

That is the scientific answer to why leaves turn different colors in the fall. The simple answer is God has a really big box of crayons!

"November's sky is chill and drear,

November's leaf is red and sear."   Sir Francis Scott

(In case you don't know what "sear" means (I didn't), it's an Old English word meaning "dry"- but, of course, that would not rhyme with "drear!")