How do trees breathe?

Yes, breathing does take place in the leaf but it is chlorophyll that actually absorbs the carbon dioxide. The carbon dioxide that they absorbed is then used with water to dissolve minerals taken up from the roots. In the winter they are partly helped by their tiny breathing pores called stomata which is in the branches. But for most of their help they go through anaerobic respiration which is just respiration without air.

Yes, they don't exactly breathe the way an animal does, but in Photosynthesis where the sun's energy is captured into sugar molecule, the process excess is carbon dioxide. This passes from the leaves (where most photosynthesis occurs) through stoma in the leaves.......openings that open and close as needed.

As to when tree leafless, the photosynthesis load is near nil, so not a problem. But there are still openings in the stems called lenticels (usually younger stems) that allow the plant to regulate gas levels inside. If you have forsythias, look at the younger stems......see the pits?

Trees do breath. You can remove all a trees leaves and it will survive and grow back. But if you cover the root system and the root collar (the bottom flare of the trunk) with a few inches of soil the tree will die from lack of oxygen. Many people come to this site asking if they can cover the root of their trees so the grass will grow better or some other reason. We tell them not to, because that's where the tree gets it's oxygen. Here is a link to a government site that explains the breathing process.

http://ohiodnr.com/forestry/urban/features/treepla...

Well deep underground they have a giant set of lungs which is connected to an opening at the top of the tree. The hole is microscopic so you can't see it just by looking at it. But it's there.

Trees absorb oxygen through their roots.