Andrew B.
Is the tree in a PLASTIC pot? If yes, dig a hole, place the tree in the hole, pot and all, then slice away the pot, and slip the tree, roots and all. into the new growing area. Add mulch and water well for the first week. Roots will never know the difference, and plant will continue to grow as before the transplant. The trick is not to mess with the roots. Do it...but don't wait too long. The growing season is coming to an end and that tree needs to be established in the new growing area before cold weather hits. Good luck.
Frank