Wych Elm
Scientific name: Ulmus glabra Huds.
Diagnostic features
Tree to 37m.
Outline ± orbicular.
Trunk dividing low down into many long spreading branches.
Leaves 8-16cm, very rough on upperside, asymmetric at base, with 12-18 pairs of lateral veins.
Petiole up to 3mm, most of it overlapped by base of long-side of leaf-blade.
Chromosome number: 2n=28.
Habitat
Native; woods and hedgerows, sometimes dominant, especially on limestone.
Distribution
Throughout British Isles, but much commoner in North & West and not native in much of Southeast.
This species is keyed out at Page 1730 in the Text Key.
Note
Two ill-marked subspecies are sometimes recognized:
Ulmus glabra subsp. glabra, with broadly obovate leaves, more southern in distribution;
and Ulmus glabra subsp. montana Hyl., with narrowly obovate leaves and typical of the North & West.
Hybrids
- Ulmus glabra x Ulmus procera has been recorded from several areas, most reliably Essex and Lincs, but is certainly rare and perhaps extremely so.
- See Ulmus vegeta(x) (Loudon) Ley (= Ulmus glabra x Ulmus minor) is abundant wherever the 2 parents meet, especially in Central England, and also elsewhere due to introductions. Plants extremely varied according to the Ulmus minor parent(s) involved and to the degree of backcrossing. Characters of Ulmus glabra detectable are rust-coloured hairs on the buds, numerous (more than l2) pairs of lateral veins, cuspidate leaf-apex, and coarse, forward-directed serration; the leaves usually have a smooth upperside. Some of these hybrids might involve Ulmus plotii as well in their ancestry. See Ulmus vegeta(x) and Ulmus hollandica(x).
- ? Ulmus x elegantissima Horw. (= Ulmus glabra x Ulmus plotii) is common within the range of Ulmus plotii. It can be told from Ulmus glabra x Ulmus minor by the erect habit often with pendent branches and the small leaves with blunt serrations. |
