As autumn approaches and our favorite trees turn all shades of red, orange and yellow, eventually these leaves will fall to the ground. But why?

Trees that shed their leaves for part of the year are called deciduous trees. It’s actually a defense mechanism for the trees to protect against severe weather. In colder areas, trees drop their leaves to survive harsh winter weather. In warmer areas, trees shed their leaves at the beginning of the dry season.

These deciduous trees, including varieties of ash, birch, cherry, maple, oak and more, have larger leaves that are easily damaged during the cold and dry weather. As the inclement weather approaches, specific hormones in the tree trigger the leaves being cut off from the central lines of tree. The tree then reabsorbs the valuable nutrients from the leaves and stores them for later use. At the end of this process, when the leaves drop, a protective layer forms over the areas where the leaves once were on the tree.