Bob: American elm is double serrated and I don't think these are (I've only looked at the close- up)

Yeah, i think you are right, i would say wych elm but the way the buds burst is different, cornish elm maybe (i doubt it) but could be english but the disease has massacred it, so if not american then rocky elm or slippery elm, but american elm could be a possibility but as auk said, it is double serrated so probably not american.