I forgot to add that juvenille English Oaks (quercus robur) tend to hang on their dry brown leaves all through winter but eventually this habit will decline and total leaf loss will occur.
When I lived in Canada I was told that the reason that oaks did not survive on the prairies was that it could not tolerate false springs i.e. a retreat back to winter following the bud break resulting in frost damage. We planted acorns from oak trees growing in my Olde Hampshire garden at Tom Musco's place in Royalston, Mass. to celebrate the raising of Pembroke Cottage a few years back. It would be interesting to discover if these trees survived and flourished.