Trees give us oxygen

basswood tree

We love trees for many reasons.

They give us shade. They're beautiful. They are homes and food sources for a variety of animals. Plus, they give us clean oxygen to breathe!

To eat, trees go through a process called photosynthesis. To do this, their leaves pull in carbon dioxide and water through tiny pores, called stomata, and use energy absorbed from the sun to turn the CO2 and H2O into sugars.

During that process, the tree releases 02, which is oxygen, from the leaves' stomata.

What's interesting is that it takes about equal parts carbon dioxide to make that same amount of oxygen. It takes six molecules of carbon dioxide to produce one molecule of glucose --- the sugar that the tree needs for its metabolism. During photosynthesis, the tree then releases six molecules of oxygen as a bi-product.

The process of photosynthesis occurs in the green parts of the leaf and stem, called chloroplasts. That means that trees do most of their work taking in carbon dioxide and releasing oxygen when their leaves are green, which is during the spring and summer.

As fall arrives and leaves change color, they can no longer do photosynthesis. Some trees with green stems are still able to do some synthesizing of carbon dioxide into sugars, mostly utilizing carbon dioxide that they give off themselves.

Trees also utilize oxygen when they break down the sugars they have created during photosynthesis to use for energy. However, they release more oxygen than they use up, so that they provide enough oxygen for you and me to breathe.