Super question, Mikey! I know everyone has seen it. Leaves on trees turn yellow, orange, red or brown and then they fall off in fall or winter. Let’s find out why!
In the spring and summer, leaves are very busy. They will take in sunlight and turn it into energy (en – er – jee) so the plant can grow. Leaves use chlorophyll (klor – a – fill) to do this, and chlorophyll is green. All spring and summer, the leaves are green because there is a lot of strong sunlight. The leaves make a lot of chlorophyll. People have made something that can turn sunlight into energy. They are called solar panels.
After summer is over, the sunlight is weaker and the day’s become shorter. There is less sunlight for the leaves, so they make less chlorophyll. The green goes away, and now we can see the other colors that are in the leaves. Did you know the yellow, orange, red, and brown are always in the leaves? It’s just covered by the green chlorophyll! But why do the leaves need to fall off?
Let’s take a look at the 3 main reasons:
- Losing leaves in the winter helps trees save water. Trees that don’t lose their leaves lose a lot of water in the winter, because it is usually pretty dry. These trees are called evergreens. Evergreens have different reasons for keeping their leaves. Trees that lose their leaves are called deciduous. (de – sid – joo – us)
- Deciduous trees can grow new leaves in the spring. In the winter, deciduous trees have no leaves. They don’t need to protect the leaves, or heal the leaves if something bad happens to the tree. New leaves will come back in the spring anyway.
- Deciduous trees don’t need to worry about animals. Animals (insects too!) still need to find food to eat in the winter. Many times, they will eat evergreen plants because they are more healthy and easier to find.