Why do leaves change colors in the fall?

Japanese Maple Leaves (Getty Images)

This time of year, it’s natural to want to go outside and hike through autumn’s spectacular colors. But why do the leaves change from green to red, yellow and orange during the fall?

Green Leaf Texture (Getty Images)

It all begins in the spring, when trees and plants produce new leaves and experience significant growth in size as well as foliage.

From spring into summertime, a compound located within the leaves allows trees and other plants to produce food.

This compound, known as chlorophyll, reacts with sunshine as well as carbon dioxide to create glucose, a type of sugar that serves as the plants’ energy source.

Plant cell with chloroplast/chlorophyll under a microscope. (Getty Images)

Chlorophyll is the color green, and so much of it is produced in the spring and summer that the overwhelming color from trees and plants is the ubiquitous shade of green.

In the fall, the decreasing amount of daylight as well as changing solar angle signal to the trees and plants that winter is coming. Leaves contain a great amount of water content, and if these were to freeze during the winter, it would cause a large amount of stress to the plant. As a result, the trees and plants gradually halt production of chlorophyll as well as divert water resources from the leaves to the trunk or branches. As the chlorophyll fades away, other compounds present in the leaves produce the vibrant colors that we see every autumn.

As the leaves become sufficiently dry, they are no longer able to remain attached to the tree or plant, and they fall to the ground during the season.