As autumn arrives and the weather gets cooler, something amazing happens to the trees. The green leaves start changing into beautiful colors like yellow, red, orange, and brown. Let’s learn why this happens and why leaves eventually fall from the trees.
Leaves are like little food factories for plants. Trees take in water through their roots and sunlight and air through their leaves. With the help of sunlight, trees turn water and air into oxygen and a kind of sugar called glucose. The oxygen goes back into the air for animals to breathe, and the glucose feeds the tree.
This important process is called photosynthesis, and it happens because of a green substance called chlorophyll. Chlorophyll makes the leaves green and helps the plant soak up sunlight.
When summer changes to fall, the days get shorter and nights get longer, meaning there’s less light. This tells trees that winter is coming. In winter, trees with big leaves can’t make food because there’s not enough light and water. So, they use the food they saved up during summer and start shutting down their food-making process.
As part of this, trees stop sending water to their leaves. The chlorophyll fades away, and the green color disappears, showing other colors in the leaves. Different trees have different chemicals in their leaves, which is why we see so many colors in autumn.
Once the leaves dry out, they fall off the tree, leaving the branches bare. Trees that lose their leaves every winter are called deciduous trees. Some trees, called evergreen trees, keep their leaves all year long. Evergreen leaves, often called needles, are small and tough, helping them survive the cold without losing too much water. This helps evergreen trees stay green even in winter, making them perfect for colder places.
Knowing why leaves change color and fall helps us appreciate nature’s cycles. Now that you understand this beautiful transformation, take a walk outside and see if you can spot different types of trees and their colorful leaves during this vibrant season!
Leaf Color Hunt: Go on a nature walk with a family member or friend and collect different colored leaves you find on the ground. Try to find at least one leaf of each color: green, yellow, red, orange, and brown. Once you have your collection, sort them by color and see if you can identify which tree each leaf came from. Discuss why you think each leaf changed to its particular color.
Photosynthesis Experiment: Create a simple experiment to understand how leaves use sunlight. Take two small plants and place one in a sunny spot and the other in a dark place for a week. Observe the changes in the plants. Discuss what you notice about the leaves and why sunlight is important for photosynthesis.
Tree Detective: Choose a tree in your backyard or nearby park and become a tree detective! Observe the tree every few days and note any changes in the leaves. Are they changing color? Are they falling off? Write down your observations and draw pictures of the tree at different times. Think about why these changes are happening and how they relate to what you’ve learned about autumn leaves.
