Small-leaved, Cornish and Jersey Elm
Scientific name: Ulmus minor Mill.
Diagnostic features
Tree to 31m.
Outline extremely various.
Leaves extremely various in size and shape but usually lessthan 10cm, ± symmetric to strongly asymmetric at base, smooth on upperside.
Chromosome number: (2n=28).
Habitat and distribution
Native at least in Channel Islands and probably in Britain; hedgerows and copses. 2 more or less uniform geographically isolated biotypes can be recognized as subspecies, but the type subspecies remains one of the most polymorphic taxa in the British flora. A number of the variants might have Ulmus glabra and/or Ulmus plotii in their ancestry.
This species is keyed out at Page 1734 in the Text Key.
Key to the subspecies:
1a. Outline ± spreading, with major branches less than 1/2 way up tree at least some of which become horizontal or pendent; leaves usually strongly asymmetric at base.
................................... Ulmus minor minor.
1b. Outline very narrow, or broad at the top, always with all main branches ascending, with no or very few major branches in lower 1/2 of tree; leaves usually weakly asymmetric at base.
...................................................................... 2.
2a. Trunk persisting to tree apex; branches numerous, slightly ascending.
............................ Ulmus minor sarniensis.
2b. Trunk ending short of tree apex; branches few, the lowest steeply ascending.
......................... Ulmus minor angustifolia.
Hybrids
- 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) involvedand 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 procera x Ulmus minor is occasionally found as isolated individuals within the range of various variants of Ulmus minor. The influence of Ulmus procera can be seen in the very broad leaves with a somewhat rough upperside.
- ? Ulmus x viminalis Lodd. ex Loudon (= Ulmus minor x Ulmus plotii) occurs in East Anglia and Central England with the parents and is planted elsewhere. The influence of Ulmus plotii is most often shown by the elongating short-shoots. |
