Inquiry Blog Post #2 Why does a tree's leaves change color in the fall?

Have you ever wondered questions:

1. Why does it happen in the fall?

2. Why do the leaves fall off after turning colors?

3. Why do some trees turn red, while others turn yellow or orange?
Did you know?

Leaves change color because the length of night gets longer. Because there is more night there is less light that the leaves are exposed to during the day.

Pigments (chlorophyl, anthocyanins, carotenoids)  influence the colors of the leaves.

Different species show particular colors in the fall. Oaks turn red or brown.

Leaves fall off because the veins in the leaf are clogging and sealing themselves off from the woody part of the tree. This triggers anthocyanins which cause leaf color.

Answers:

1. A decrease in the amount of light during the day starts the color change

2. The veins or tubes begin to clog and seal off, this brings on the presence of anthocyanins. Once the leaf has completely sealed off from the woody part of the tree it will drop.

3. The color the leaf changes depends on the species of tree. Oaks turn red and brown while poplars turn yellow.
Wonder words to know and use:
chlorophyll-makes photosynthesis happen, green color in leaves

carotenoids- produce yellow and orange color

anthocyanins-appear as leaf veins clog, red colors in leaves
pigment-a chemical compound that shows a specific color