Why Leaves Change Color in the Fall

Trees do many things to get ready for cold winter days. They must send all their sap underground and store it in their roots. If the sap stayed in the branches and the trunk it might freeze in the cold winter air. Anywhere the sap freezes that part of the tree will die and stop growing.

The trees also stop making food. All the green color in the leafs is the food the tree makes from sunlight and air. The green food is called chlorophyll. The chlorophyll is turned into sugar and sent from the leaves to different parts of the tree. Some is stored in the branches, some is stored in the trunk and some is stored in the roots. Some is even stored in buds so they can turn into leaves and flowers in the spring after the cold winter.

As all the green food disappears the leaves start to change color. Some trees leaves will turn red, some will turn yellow, and some will turn orange. The red, yellow, and orange color has always been in the leaf but you couldn't see it because the green covered it up.

After every tiny bit of food has been moved from the leaf and all the sap has gone from the branch the leaf will come loose from the branch and float to the ground. Then you will know it is fall and the trees are ready for winter.

Leaf Rubbings

You can see what leaves will look like in the fall by making leaf rubbings.

Supplies needed

• Regular notebook or typing paper

• Crayons or chalk

• Tree leaves from your neighborhood
  

Collect a few tree leaves.

Take one of your leaf samples and place it on a flat surface or table.

Take a sheet of notebook or typing paper and lay it on top of the leaf.

Remove the wrapper from around your crayon.

Turn the crayon sideways and rub it back and forth across the paper.

Your leaf will magically appear in a new color.

back to top