Here's one of those "you're a forester, what kind of tree is it" type of deal. I haven't seen this tree, but I'm told that it is in someone's yard in southeastern PA, fairly close to Philadelphia. It is supposed to be higher than a 2 story house, so that pretty well rules out a shrub. Here's a picture of the leaves:

and here's a closeup of the bud:

The leaves are about 3" long, so they're a lot shorter than the typical oak leaves on our native trees. I'm thinking its some type of oak, but could be wrong. I really stink at ornamental species.