The elm with which we are most familiar in the North is the wych elm (U. montana), easily to be distinguished from the English elm by the fact that it throws up no suckers from the root, whereas the English elm hardly ever ripens seed, and propagates itself entirely by suckers which it sends out as colonists to an astonishing distance—50 yards and more. There are exceedingly few authentic records of the English elm ripening seed in Great Britain; on the other hand, the wych elm sometimes produces a prodigious crop. In the spring of 1909 this tree presented a curious appearance. The foregoing summer had been a very warm one, stimulating the wych elm to such extraordinary efforts at reproduction that, before the leaves appeared, the trees seemed to be covered with fresh young foliage, which was really the crowded leaf-like seed vessels. In June these leaf-like membranes had become dry scales, each acting as parachute to a single seed, so that, under a hot sun and a high wind, the air was full of them—so full that they actually choked the eave-gutters of my house. Each of these little monoplanes carried the potentiality of a majestic forest tree; given a suitable resting-place, any one of these minute seeds might develop into an elm like those at Darnaway, in Morayshire, which in 1882 were 95 feet high, with clean boles up to 24 feet. So great was the exhaustion following upon the abnormal seed crop of 1909 that some of my elms were crippled by it, and two or three died outright.[9]
WYCH ELM (Ulmus montana)
To produce well-shaped wych elms, timely pruning is essential, followed by close forest treatment, for no other tree spreads more wildly and wantonly, and unless means are taken to keep a single leader on each, the result will be very different from those lordly examples which stood, not many years ago, on the banks of the White Cart at Pollok, four of which were figured by Strutt in his Sylva Britannica in 1824. The largest of these measured in that year 85 feet in height and 11 feet 10 inches in girth, and contained 669 cubic feet of timber. Two of this group were blown down in the great gale of 22nd December, 1894, and the remaining pair were felled in 1905, being respectively 90 and 96 feet high. The age of these giants was shown by the annual rings to be about 300 years.
The weeping elms which one sometimes sees in gardens is a variety which originated in a Perthshire nursery about one hundred years ago. It is very ornamental, though it never attains much height, being perfectly flat-topped. As it can only be propagated by grafts, a sharp lookout must be kept to prevent the stock outgrowing the scion.
The wych elm is indigenous over the whole of the northern part of Great Britain, the largest recorded being at Studley Royal, in Yorkshire—105 feet high and 23 feet in girth at 5 feet up in 1905. As an element of the primæval Scottish forest, the wych elm must have been held in high esteem, judging from the number of Gaelic place-names commemorating it. The old Gaelic name for it was leam, plural leaman (pronounced "lam" and "lamman"). Ptolemy's Leamanonius lacus is now Loch Lomond, the lake of elms, out of which flows the Leven, which is the more modern aspirated form leamhan (pronounced "lavan"); and we find the same association of names in eastern Scotland, where the Lomond Hills overlook the town of Leven. The Lennox district was formerly written Levenax, which is the adjectival form leamhnach (lavnah), an elm wood. The rivers Lune and Leven in Lancashire (Ptolemy's Alauna), the Leven in Cumberland, and the Laune at Killarney all seem to indicate the former existence of elm woods on their banks. In the name Carlaverock is probably preserved another derivative—caer leamhraich, the fort among the elms.
It was long supposed that the English elm (U. campestris) was not indigenous to England, seeing that it never propagates itself in these islands by seed. Its presence was explained by the convenient device of attributing its introduction to the Romans; but there is not a shred of evidence in support of this conjecture. The elm of Italy is quite a distinct species, according to Elwes and Henry, a fact with which Shakespeare, though familiar with "Warwickshire weeds" (as elms are called near Stratford-on-Avon), may not have been acquainted when he made Adriana plead with him she believed to be her husband:
Come, I will fasten on this sleeve of thine;
Thou art an elm, my husband, I a vine;
Whose weakness, married to thy stronger state,
Makes me with thy strength to communicate.
The English elm, however, grows luxuriantly in Spain, and ripens seed abundantly there, the tradition being current that it was introduced from England to the Royal Park at Aranjuez when Philip II. was laying out that demesne. Dr. Henry, however, considers it not improbable that this tree is truly indigenous in Spain, and that it is certainly so in the southern counties of England, where, as aforesaid, it reproduces itself only by suckers. Other examples are not wanting of certain plants yielding to climatic conditions, by resorting to reproduction by suckers and ceasing to produce seed.