How sad to discard an old Christmas tree! If you have the time and energy, I suggest the following:
• Take the tree into your yard and using a handheld clipper, trim off as much of the foliage as you can. Or even better, use an electric hedge trimmer.
• Cut the branches into smaller pieces and spread it around between plantings to act as mulch. It'll keep down weeds while decaying and adding nutrients into your soil.
• Alternately, you can toss the cuttings into your compost.
Now as for the trunk, you can cut it with a saw into maneagable sections. And if you are the adventurous type, let the wood dry outside for a few months, and you can burn it in a fireplace or outdoor firepit. Or for the ultimate in holiday recycling, you can go to the extreme and carve the dried wood into Santa figures to decorate next year's tree! Or maybe not. But do avail yourself of the free mulch/compost if you can.
What became of my Christmas tree.