Since trees cannot walk or put on a cloak to keep warm, they do the next best thing in preparing for the bite of the cold. They pay attention to their most vulnerable parts of their frame and that is, their leaves. Leaves are usually green in color and that comes from a pigment called chlorophyll. Think of the leaves as a fancy kitchen that uses sunlight and other good things provided by nature to manufacture food for the trees. In making the food for the trees, the leaves also produce water. Leaves have holes or pores in them through which this water is given off. We perspire through pores in our skin and the trees respire through pores in their leaves. 

In the winter we can actually get water from ice by chewing it or simply waiting for it to melt. Trees need water as well but of course, they can’t chew ice! They do wait for it to melt but that sometimes takes a long time. The trees would suffer and will not be able to survive without water for the entire winter. So in order to save water, the trees do something special. They remove the parts of their structure through which water is lost. And if you guessed that it is the leaves, you are correct! 

Before they get rid of their leaves, they do two things. All the water that is in the leaves is removed and all the chlorophyll is also removed. Next time you are learning outside pick up one of the discarded leaves and see how dry and brittle it is. The trees are dropping their leaves right now in preparation for the winter season ahead. If we didn’t know better, we would think that they are dying but in fact, they are going into a stage of dormancy and they do look as if they are asleep. In a few more weeks, we will see the trees standing naked with their unclothed branches pointing to the wintry skies.  

I am sure you do know that some trees keep their leaves and they remain green even throughout the cold time. How they actually do this will be discussed in the Part Three of our story.

Check out Playtime in the Autumn Leaves on your iPad; its a nice story of bears enjoying the beauty of the autumn leaves.

Dr. Keith Yearwood