I just read that only growing trees burn carbon dioxide and give off oxygen. But that full grown trees give off carbon dioxide as do full grown plants. Since trees account for 51% of all carbon dioxide and burning fossil fuels only supply 3%. If we need to drastically cut the 3% wouldn't it make more sense to cut down all the trees?
http://www.denisdutton.com/cooling_world.htm
Mature trees do not absorb co2. In fact it takes a growing forest of 40 acres a year to supply enough oxygen for 1 person. It helps but is not a savior.
Since the beginning of the 1900's the scientific community has been going back and forth on whether there is global warming or global cooling. In the 70's we were told that global cooling was going to usher in a new ice age and that we needed to cut carbon dioxide emissions or the earth would freeze over. (Newsweek Magazine April 28th 1975)