Question
We bought a flowering pear and did not get it into the ground as soon as we'd like.  I think it needed more water than we gave it before it actually got planted.  The leaves appear to be dead (except for the ones at the top), but the trunk of the tree is still green when we scratch the trunk.  Will it come back to life or is it a lost cause?

Answer
It is still alive at this point and should leaf out next spring. I would water it once a week if it does not rain. Assuming this is a small tree water with about 3 gallons of water each week. This should be done during the winter until or if the ground does not freeze--the root system will need the water to grow. If you have not done so mulch around the tree with not more than 3 inches of mulch this will help hold the moisture.  

Next spring there maybe some branches that have died these can be pruned off after full leaf out.