They don't chop down the tree, instead they deliver a live tree in a pot. You decorate it, water it, and enjoy it. When the holiday is over, they pick up the tree and it goes back to the farm to grow another year. You can even request the same tree year after year, so you can see it grow.
The trees are kind of pricey (not including delivery) and you have to reserve super early. I missed out this year, but I'm definitely getting one next year, and the year after that, and the year after that.