I don't think those pictures are going to be
enough for most people to be able to make an ID unless they're already familiar with that particular type of tree. In fact, the pictures almost look like two different plants to me! The first one looks like a young tree with a clear trunk while the other one looks like a shrub of some sort, with several main stems.
From what you've given us I can see that it's obviously deciduous with oval leaves that are possibly silver on the underside. That won't get us very far. What I can't tell is if the leaves are simple or compound; smooth, toothed, or serrated; the nature of the midrib/veins; etc., etc. You
should give us a close-up of the leaves, if possible.
It would also be helpful to get a better view of the buds on the branches as well as the bark.