The easiest way to identify elms is by looking at the samaras, but they are likely long gone this time of year. Leaves might tell you what you need to know. It's probably either Ulmus rubra or Ulmus americana. The top sides of the leaves of Ulmus rubra are very rough, while the top sides of the leaves of Ulmus americana are usually relatively smooth. Just judging by the pictures, I'd guess Ulmus americana.
