A tree up to 120, or even 150 ft high, with a trunk 6 ft or more in diameter; young shoots hairy. Leaves roundish ovate, to broadly oval, very unequal at the base, terminated by a short, abrupt point, coarsely and doubly toothed, 2 to 31⁄2 in. long, about two-thirds as wide, dark green and very harsh to the touch above, paler beneath and downy all over, with conspicuous tufts of white down in the vein-axils, along the midrib, and at the base of the cheif veins – of which there are ten to twelve pairs. Flowers clustered closely to the branchlet, opening early in the year, reddish. Samaras roundish, 1⁄2 in. across, not downy, bearing the seed close to the notch at the top.
In old books on trees the English elm is usually said to be a native of Europe introduced to Britain at the time of the Romans. It is now fairly certain that it is genuinely wild nowhere but in southern and central England. The English elm produces fertile seed extremely rarely. I have not myself seen a genuine seedling, but Henry states that he raised four plants out of twenty batches of seed sown in 1909. In many parts of southern England the elm is the dominant tree, especially in hedgerows; all these trees, however, have sprung from root suckers, which the elm produces freely, and which afford the best means of propagation.
The origin of the English elm still remains a mystery. It occurs in some parks and gardens of Spain, but apparently always planted, and there is no evidence that it was ever introduced to England from Spain. On the other hand, there is a tradition that the Spanish trees originally were sent from England. Against its being a genuine native of Britain, there is the curious fact that it is almost invariably infertile.
As a tree in the English landscape the elm impresses one by its noble stature and bulk, its rich leafiness, and its singular beauty in winter when the finely fretted outline of its naked branches shows in delicate tracery against the sky. In the autumn the foliage dies off rich yellow, and lingers on the branches longer perhaps than that of any of our native trees. This elm has an unfortunrte propensity in age of dropping its limbs, which snap off without any warning. This usually happens on still evenings in late summer and early autumn when the trees are still in full leaf. It is also liable to occur during a heavy rain following a period of heat and drought. This habit makes the elm a very unsuitable tree to plant in crowded thoroughfares.
The timber of elm is valuable for its toughness and the absence of any tendency to split. It has also considerable beauty of graining and colour. Kept permanently dry or permanently wet, it is very durable. At one time, before the introduction of iron pipes, hollowed-out trunks of elm were used as water-pipes.
To the above account, taken from previous editions, there is little to add, except that it would now be more appropriate to put the whole passage in the past tense so far as much of England is concerned. Most authorities now accept that the English elm is endemic to England, occurring on the continent only as a planted tree. Reports of its occurrence on the continent were in part the result of nomenclatural confusion. To British botanists U. campestris has always meant the English elm, and it may have been assumed that continental botanists were using the name in the same sense, when in fact U. campestris as understood by them was U. carpinifolia or sometimes a hybrid of it. There may also have been confusion between U. procera and hybrids of the Hollandica group with leaves downy beneath as in our species, or even with U. canescens. But the origin of the English elm remains a mystery. Helen Bancroft suggested that it may have arisen in this country from hybridisation between U. carpinifolia and U. glabra. There is also the possibility that it may have originated somewhere in the western parts of continental Europe and subsequently become extinct there.
It was suggested in previous editions that the infertility of the English elm is actually a consequence of its abundant production of suckers from the roots, but this theory is disputable, to say the least of it. Many species of trees and shrubs have the ability to spread by this means without thereby losing the ability to reproduce themselves sexually. A more conventional explanation is that owing to its suckering habit it has, with the help of man, been able to maintain itself, becoming widely spread despite its infertility. It has been found that U. carpinifolia and at least some of its hybrids are as a rule self-sterile and therefore would not set fertile seed when grown in isolation or in the company only of other members of the same clone. But in the case of the English elm a further explanation for its infertility has been advanced, namely that the flowers are frost-tender. This might help to explain why no proven hybrids between U. procera and other elms exist, though it has been suggested that certain anomalous elms are the result of crossing between it and U. carpinifolia.
For U. procera var. australis (Henry) Rehd. (U. campestris var. australis Henry) see Elwes and Henry, op. cit., p. 1904. The elm described by Henry is really rather remote from U. procera and probably a hybrid, planted in S. France, Italy, etc.
cv. ‘Argenteo-variegata’ (‘Foliis Variegatis’). – Leaves conspicuously blotched, striped and margined with creamy white (U. campestris argenteovariegata West.; U. c. foliis variegatis Lodd.). This sport has been in commerce since the 18th century. Its suckers are also sometimes variegated.
So far as is known, there are no other cultivars that can with any certainty be referred to U. procera. Those placed under it in Rehder’s Bibliography are disposed of as follows:
f. aurea (Morren) Rehd. – See under U. ‘Viminalis’.
var. berardii (Simon-Louis) Rehd. – See U. ‘Berardii’ under U. carpinifolia.
f. marginata (Kirchn.) Rehd. – See under U. ‘Viminalis’.
f. purpurascens (Schneid.) Rehd. – This name is founded on a small-leaved elm put into commerce under the name U. campestris myrtifolia purpurea; it had purple-tinged leaves about 1 in. long, downy beneath.
f. purpurea (Wesm.) Rehd. – This appears to be the purple-leaved hybrid elm mentioned under U. angustifolia.
f. vanhouttei (Schelle) Rehd. – See U. ‘Louis van Houtte’ below.
U. ‘Louis van Houtte’ (‘Vanhouttei’). – Leaves entirely yellow, retaining their colour throughout the summer, scabrid on both sides; branchlets hairy (U. campestris ‘Louis van Houtte’ Deegen; U. montana f. lutescens van Houttei Hort. ex Schelle; U. procera f. vanhouttei (Schelle) Rehd.).
Although usually placed under U. procera this elm is of uncertain status. It is very susceptible to Dutch elm disease and it was recorded in the last edition of this work that two healthy trees at Kew in the Pagoda Vista succumbed in 1931 only a few months after the first visible evidence of the disease.