I reached 900 miles today, so needless to say; I’ve been running and walking a lot. It’s a beautiful time to walk around my hometown with many trees turning red, yellow, and orange.
Today, as I admired the fall colors, I wondered why they change. I had a vague notion that it had something to do with a lack of chlorophyll, but I wasn’t sure why. The reason is fascinating, and I’m glad I did some research.
Different chemicals cause the red, yellow, or orange of a fall leaf. Those chemicals are always present in the leaf, but the color is hidden when the tree is making food during the summer. The green comes from chlorophyll. In the fall, trees stop making food, and the green disappears, revealing the fall color that was there all the time.
There is a PDF on the Science Bob website that explains which chemicals create each color. It could be a useful handout for teachers or anyone interested in science.