For U.S. Residents only

Is it possible to be allergic to Christmas trees?

I'm worried about getting a live Christmas tree. I've heard that people can be allergic to them, and I don't want my guests to feel sick while visiting for the holidays. 

Not likely
It is not likely that you are allergic to the Christmas tree itself. However, it is possible that there could be other allergens present such as mold that got into the needles and branches.