We finished our tree inventory at today's meeting, and were able to add another tree to our list. We are now fairly sure that the the scrubby stuff which we had previously dismissed as a form of birch is actually elm (Ulmus sp.) It appears that the identification of elms is a complex business, with botanists disagreeing over how many species (and hybrids) there actually are. To give you an idea of the problem, I've downloaded a couple of elm identification guides and added them to our Library.
Although our elms are shrubby growths, clustered around the north-east corner of the pond and apparently suckering, we have found one or two in good locations where they can be encouraged to grow larger. However, we do not expect them to reach the stature of the elms of the English countryside before Dutch Elm Disease decimated them, and they may not be the same species as those.