From Green to Yellow: The Transformation of Leaves

As you take that fall foliage tour in northern Michigan or simply rake leaves in your yard, start a family discussion about why the leaves change from green to red, yellow and orange.

Here's the science behind the process:

Plants know when autumn is coming because the days get shorter. During the winter, there isn't enough sunlight for photosynthesis to occur.

Photosynthesis is how trees get their food. It happens when sunlight, water and carbon dioxide combine to produce glucose, which nourishes the trees.

Chlorophyll – which makes the leaves green – fades to reveal yellow and orange leaves. Bright purple and red leaves are found on maple trees, and result when glucose is trapped in the leaves after photosynthesis stops.

The brightest colors occur when late summers are dry and autumn days are bright and sunny with cool nights.

For more information: visit www.sciencemadesimple.com/leaves