This is the time of the year that our trees put on a show. It starts in October and lasts until the leaves fall. The normally green leaves of many deciduous trees and shrubs, now begin to take on the autumn shades of red, yellow, purple, orange and brown. We are very blessed in our area to get a beautiful palette that paints our hills in golden hues. Children are often told that the crisp nights and frosty winds cause the leaves to change colors.
Have you ever thought about how it happens? The leaves are green because of the presence of a pigment known as chlorophyll. It is the engine that feeds the plants as they grow in the spring and summer. The chlorophyll’s green color dominates and masks out the colors of any other pigments that may be present in the leaf.
In late summer, as daylight hours shorten and the temperatures cool, the veins that carry fluids into and out of the leaf are gradually closed off by a new layer of special cork cells. During this time, the chlorophyll begins to decrease and the hidden pigments of yellow and orange are revealed, and red pigments are synthesized once half of the chlorophyll has been degraded.
It is also true, that trees communicate with their surroundings, and a tree’s colors may also be signals to beneficial and parasitic insects, displaying the trees health and vigor. Just as the biology of a large stand of trees of the same species, can show a ripple of biological changes move across the grove of trees, as stress chemicals are released from trees under attack, it might be true that the fall colors may be sending signals to their surroundings.
This richness and diversity of species, creates a yearly masterpiece of natural art that blankets the region, luring droves of city bound neighbors to drive our hills and- for at least a day's outing, enjoy the natural bounty. It is a glorious time!