If you are worried about greenhouse gasses and global warming, then I have some Christmas advice for you. When you are done with your Christmas tree, do NOT take it to one of those "recycling" locations most towns have. The recycling process is typically chipping and mulching the trees, which just accelerates their decomposition into greenhouse gasses. If you are really concerned about catastrophic warming, you want to use your tree as a carbon sink. Have it shrink-wrapped in some sort of plastic what won't biodegrade and then landfill it -- the deeper it is buried, the better. Those folks trying to get you to "recycle" your tree are secretly in the pay of the Koch brothers and trying to trick you into ruining the environment.