Ulmaceae
Ulmus . . . . . Elm
Leaves characteristically asymmetric at base, but generally very difficult to distinguish the many individual species/subspp. and hybrids that have been proposed
Ulmus glabra . . Wych elm
The commonest sp. in Scotland - largely resistant to Dutch elm disease; buds with many rust-coloured hairs; lvs large and v rough on upper side
Camperdown elm - deformed sport now planted in several places (e.g. this example in Toronto)
Ulmus procera . . English elm
Largely killed by Dutch elm disease, but in many places young shoots reappear before being killed by the disease; leaf width/length ratio >0.75
Other spp. (hard to distinguish) include U. minor and its subspp. (e.g. small-leaved and Jersey elms) which have lvs smooth on upperside and lvs with width/length ratio <0.75