10 / 08
Why Do Leaves on Trees Change Colors in the Fall?
One of the most delightful things about autumn is how some trees’ leaves change color from green to bright yellows, oranges, reds and browns in preparation for winter. Although this is a common occurrence, our tree removal professionals in Georgia wish to explain why trees undergo this process.
There are several different reasons why leaves turn the colors they do, but according to our professionals in tree removal in Atlanta, the main reason they begin to change is the reduced amount of light that reaches the leaves after the autumnal equinox. The equinox is the turning point when the long days of summer finally have shortened enough to be equal to the length of the night. After the equinox, the days are shorter and the nights are longer.
This reduced light triggers chemical changes in deciduous plants. Although you can’t see it, these changes encourage a corky wall to form between the leaf stalk and the branch it attaches to. Our Atlanta tree service team notes that this blockage eventually will seal off the vessels that supply the leaf with nutrients and water, leaving simple sugars trapped in the leaves. The lack of nutrients and reduced light causes the chlorophyll in the leaves, which produces the green color, to die.
Once the chlorophyll dies, the other colors in the leaves are able to shine through, bringing out combinations of yellow (carotene) and red (anthocyanin). These colors are in the leaves throughout the year, but the green chlorophyll masks them.
The trapped sugars within autumn leaves are responsible for the vividness of the leaves’ colors. Additional anthocyanins are manufactured within the leaf by the trapped sugars when they are exposed to sunlight. Our Alpharetta tree specialists have found this encourages the leaves to become more vibrantly colored when there are several bright, sunny days in a row. It also explains why the leaves become more pastel in color if the fall is a rainy one.
Not All Leaves Change
Georgia is famous for its pine trees and other evergreen varieties. These trees have long, thin, blade-like leaves that we call needles. These trees’ leaves do not change color at any specific time of the year. The only time these leaves change color is when they have died and are in the process of falling off the tree. Submit a free estimate form to Yellow Ribbon Tree Experts if you see whole sections of an evergreen going brown, you may have an issue with tree death or disease.