Why Leaves Change Color
Frost and cold air are often thought of as the reasons the leaves turn color every fall. It's not the frost or the cold air but rather the inability to replenish Chlorophylls (which occurs a few weeks before the first frost). A chemical change brought on by shorter days and cool nights cause leaf activity to diminish. Chlorophylls absorb and use the energy of red and violet wavelengths of sunlight to make simple sugars and starches that trees use for food.
The brilliancy of the color depends on:
1) How healthy the leaf is before the change
2) Availability of water before the change occurs
3) Temperature changes can accelerate the process, but the shortening of the days starts it
On average the leaves peak in color in Garrett County, Maryland around tenth of October. The leaves are now at or a bit past peak west of the divide in Garrett County and south into the Canaan Valley. The 45th annual, Autumn Glory Festival runs from the ninth through the thirteenth. The colors up there should be magnificent. The usual peak along Skyline Drive is between the sixteenth and the twentieth of this month.
Across the suburbs the peak is usually in late October with downtown peaking in early November. We had our fourth wettest June with nearly ten inches of rain but have been rather dry since then. We'll have to wait and see if this dry spell will hinder or maybe enhance the fall colors in the Shenandoah Valley and also our colors in the immediate Metro Area. We'll update the process on WUSA 9 News every night in the fall and on our website @ wusa9.com.