I want everyone on the internet to be very clear on this point

Humans need to breathe oxygen. We expel carbon dioxide.

Trees do the opposite. They take up carbon dioxide (and water). They expel oxygen. (side note: it's not a direct conversion, this CO2 to O2. The O2 comes from the water).

If I read another student paper wherein I am told that trees produce carbon dioxide, I might just scream. I thought we all learned this in first grade.