This tree is located in an urban park in USDA zone 3a with winter temperatures to -40 deg Celsius. It has a trunk about six inches in diameter and is about thirty feet tall. In the winter I mistakenly identified it as Quercus macrocarpa or the Bur oak due to the prominent corky wings on the branches.
Now that the tree has leafed out it looks more like a beech tree with serrations on the leaves. What species is this tree?