I do understand protecting old growth, second and even third growth forests if they are in areas impacting habitat. Urban forests and green spaces are a particular interest for me. However, with the exception of certain species of trees, the practice of harvesting responsibly is not a bad thing. It can in fact help keep healthy forests intact.
I don't advocate any clear cutting of mature forests or standing groves like many paper/wood product companies do or the slash and burning of pristine forests to grow Palm Oil trees. Tree farms (Not Forest, Urban or Natural) managed in a manner that is environmentally responsible are a different thing, so I am not sure just how large the harm is.
All growing matter decays and as it decays it will release the carbon contained within. Leaves, bark, the flowers planted in everyone's gardens.
If anyone is uncomfortable with the cutting of Christmas trees, then a potted one is an option. Just make sure you have space to plant it or have someone who will take it. Remember the beautiful Blue Spruce in the pot becomes:
"A magnificent sight of silver blue-green spruce. Rated one of the most popular evergreens. It grows well while young and matures at 50-75'; 10'-20' spread in the landscape, up to 135' and 35' spread in the wild." Arbor Day Foundation
Since I referenced the Arbor Day Foundation, take a quick trip to their site and you will see a link to their Lodge which is built partly of wood. The pictures of the interior show the use of wood products in daily activity. I suspect they received their wood from sustainable practices, but in truth I have not asked them. You can also type in “sustainable” and review some interesting articles.
Another great read is at the National Geographic website. Click on tab and look for the “The Case of the Missing Carbon.”