Well the consensus seems to be that it might be a wild pear. I hiked back down to look at it after perusing pictures on the net. I wanted to see what shape the leaves are and if the branches end in a thorn. Guess what! It doesn't have any leaves and the thorns are perpendicular to the branch. I played with some automatic settings on my camera to get these pictures. Looks like the blossoms are almost gone. I'm going to keep a watch on it this year to see if any fruit appears.