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more regular appearance, not start
1232 ing off at right angles, but forming its shoots more acutely with the parent branch; neither does the spray of the elm shoot, like the ash (fig. 1046. in p. 1222.), in regular pairs from the same knot, but in a kind of alternacy. It has generally, at first, a flat appearance; but, as one year's shoot is added to another, it has not strength to support itself; and, as the tree grows old, it often becomes pendent also, like the ash: whereas the toughness and strength of the oak enable it to stretch out its branches horizontally to the very last twig.” (Ibid., p. 113.) As an ornamental tree, it is used, both in Britain and on the Continent, more especially in France and Holland, for planting in avenues, particularly in public walks. For this purpose it is well adapted, from the comparative rapidity of its growth in any soil, the straightness of its trunk, the facility with which it bears lopping, the denseness of its foliage, its hardiness, and its longevity. It has also the great advantage of requiring very little pruning, or care of any kind, after it has once been planted. There are many fine avenues of elms in France, particularly those in the Champs Elysées and at Versailles; and in Holland, at the Hague. In England, the principal public elm avenues are in St. James's Park, and at Oxford and Cambridge; but there are also some very fine ones at gentlemen's seats, especially at White Knights, Littlecote Hall, and Strathfieldsaye.
Poetical and historical Allusions. The ancient poets frequently mention this tree, which, in common with many other barren trees, was devoted by them to the infernal gods. The Greeks and Romans considered all the trees which produced no fruit fit for human use as funereal trees. Homer alludes to this when he tells us, in the Iliad, that Achilles raised a monument to the father of Andromache in the midst of a grove of elms.
“ Jove's sylvan daughters bade their elms bestow
A barren shade, and in his honour grow.' Ovid tells us that, when Orpheus returned to earth after his descent into the infernal regions, his lamentations for the loss of Eurydice were so pathetic, that the earth opened, and the elm and other trees sprang up to give him shade. Virgil, in his Georgics, mentions that the Roman husbandmen bent the young elms, while growing, into the proper shape for the buris, or ploughtail. (See Georg. i. ver. 170.) The use, however, which the Romans made of the elm, as a prop to the vine, has given rise to the most numerous allusions to the tree by poets, not only ancient, but modern. Ovid makes Vertumnus allude to it, when he is recommending matrimony to Pomona.
"• If that fair elm,' he cried, " alone should stand,
No grapes would glow with gold, and tempt the hand;
'Twould creep, a poor neglected shrub, below.'" Milton, in describing the occupations of Adam and Eve in Paradise, says,
-" They led the vine
His barren leaves.'
In the early ages of Christianity, the hunters were accustomed to hang the skins of the wolves they had killed in the chase on the elms in the churchyards, as a kind of trophy.
Soil and Situation. ““ Narrow-leaved English elms,” says Mitchell, “abhor clays, and all moist soils. I saw a line of them at Beaulieu Abbey, in Hampshire, 50 ft. or 60 ft. high, not more than 4 ft. or 5 ft. in circumference; all hollow, from the root to the top, as if they had been bored for water pipes. They grew on a sandy, marly, wet, heathy soil.” (Dendrologia, p. 36.) “ The propriety of planting the elm,” Marshall observes, “ depends entirely upon the soil : it is the height of folly to plant it upon light sandy soil. There is not, generally speaking, a good elm in the whole county of Norfolk : by the time they arrive at the size of a man's waist, they begin to decay at the heart; and, if not taken at the critical time, they presently become useless as timber. This is the case in all light soils : it is in stiff strong land which the elm
delights. It is observable, however, that here it grows comparatively slow. In light land, especially if it be rich, its growth is very rapid; but its wood is light, porous, and of little value, compared with that grown upon strong land, which is of a closer stronger texture, and at the heart will have the colour, and almost the hardness and heaviness, of iron. On such soils the elm becomes profitable, and is one of the four cardinal trees, which ought, above all others, to engage the planter's attention; it will bear a very wet situation.” (Planting and Rural Ornament, ii. p. 431.)
Propagation and Culture. The common elm produces abundance of suckers from the roots, both near and at a great distance from the stem; and throughout Europe these afford the most ready mode of propagation, and that which appears to have been most generally adopted till the establishment of regular commercial nurseries; the suckers being procured from the roots of grown up trees, in hedgerows, parks, or plantations. In Britain, the present mode of propagation is by layers from stools, or by grafting on the U. montàna. The layers are made in autumn, or in the course of the winter, and are rooted, or fit to be taken off, in a year. Grafting is generally performed in the whip or splice manner, close to the root, in the spring; and the plants make shoots of 3 ft. or 4 ft. in length the same year. Budding is sometimes performed, but less frequently. On the Continent, plants are very often procured from stools, simply by heaping up earth about the shoots which proceed from them. These shoots root into the earth; and, after growing three or four years, during which time they attain the height of 10 ft. or 15 ft., they are slipped off; and either planted where they are finally to remain, or in nursery lines. When they are transplanted to their final situation, the side shoots are cut ofl*; and the main stem is headed down to the height of 8 ft. or 10 ft.; so that newly planted trees appear nothing more than naked truncheons. The first year, a great many shoots are produced from the upper extremity of each truncheon; and in the autumn of that year, or in the second spring, these shoots are all cut off but one, which soon forms an erect stem, and as regular a headed tree as if no decapitation had previously taken place. (See Gard. Mag., vol. ii. p. 226. and p. 461.; and Annales de la Soc. d'Hort. de Paris, t. xviii. p. 360.) This corresponds with Evelyn's recommendation to plant trees about the “scantling of your leg, and to trim off their heads at 5 ft. or 6 ft. in height. Cato recommends 5 or 6 fingers in thickness; adding that you can hardly plant an elm too big, provided you trim the roots, and cut off the head. All the avenues and rows of elm trees in Europe were planted in this manner previously to about the middle of the eighteenth century; and, according to Poiteau (Ann., I. c.), the same practice is still the most general in France. The late Professor Thouin, in his Cours de Culture (tom. ii. p. 231.), argued against it, and had some avenues planted in the Jardin des Plantes, without cutting off the heads of the trees; but, besides being found much more expensive, from the necessity of taking up the plants with a greater quantity of roots, transporting them to where they were to be planted with greater care, and preparing a wider pit to receive them, it was found that they grew much slower for the first 3 or 4 years than those that had been decapitated. The only advantage proposed to be gained by planting trees with their heads nearly entire is, that of preserving the centre of their stems from being rotted, in consequence of the water entering at the end made by the decapitation; but
this, it is proved by the practice in Belgium, is only an imaginary evil, provided the saperfluous shoots are removed from the upper extremity of the decapitated tree the second year, and the head formed with common care by future pruņings. (See the very instructive article by Poiteau, already referred to, in the Annales, and also the account of the Belgian practice, in the Gardener's Magazine, vol. x. p. 8.) In Britain, young elm trees, having been two or three times transplanted in the nurseries, are placed in their final situations without heading down; and in our moist climate they grow vigorously the first year, and require very little pruning. On the Continent, owing to the greater warmth of the summers, and the consequent increased evaporation from the leaves, plants are liable to be killed when transplanted with all their branches on; and, hence, the mode of denuding the plants just described is that generally practised. In France and Belgium, the narrow-leaved elm is the most common tree planted by road sides, and along the boulevards and streets of towns and cities; and, in such cases, a large pit is previously dug, 4 ft. or 5 ft. in diameter, and from 2 ft. to 3 ft. in depth ; and a considerable portion of rich fine mould is placed in immediate contact with the roots of the trees, and the pit filled up with the best part of the soil which had been previously dug out of it. During the first summer, water is regularly supplied; and the trees, or rather stumps, grow freely; very little attention is required afterwards, except to encourage the leading shoot, and to shorten in the lateral branches, so as to encourage the plant to assume a tree-like form. In the neighbourhood of Paris, and in the south of France, U. campéstris, and several of its varieties, occasionally bear seeds; and these are sometimes sown by the nurserymen, in order to procure new sorts; and by the managers of the national forests, in order to obtain numerous plants at a cheap rate. The common English elm very rarely produces seeds in England; nevertheless it has done so in a few places, and one of these is Lea Park, near Littlebourne, about four miles from Canterbury. Mr. Masters of Canterbury has only known seeds twice ripened in this park; and one of the times they did not germinate. From those which did he obtained U. c. viminàlis, and nearly a score other very distinct varieties, which, however, from the nuinber of varieties already existing, and the little demand for them, he did not consider worth keeping separate, and giving names to. strícta, and some other varieties of the common elm, as well as the species, flower very profusely every year, but scarcely ever ripen seeds.
It is observed by Bosc, that the more remarkable varieties, such as the twisted elm, the broad-leaved elm, the lime-tree-leaved elm, &c., come tolerably true from seed, speaking of the mass of young plants ; but that among these are constantly produced numerous subvarieties. The seeds fall from the trees as soon as they are ripe ; and, being swept up, are sown immediately in beds of light rich soil; the seeds being placed about 1 in. apart every way, and covered to the depth of about an eighth of an inch. The plants come up the same season, and are fit for transplanting into nursery lines in the autumn. Of all the European timber trees, not belonging to the coniferous family, except the Lombardy poplars, the narrow-leaved elm requires the least care or pruning after it is planted; and, at the same time, no tree will bear better than it does the knife or the shears. All the branches may be cut from the stem, except a small tuft at the top; and still the tree will grow vigorously, affording, where that mode of feeding cattle is considered profitable, an ample crop of branches every three or four years. When headed down to the height of io ft. or 12 ft., it is very prolific of branches, as a pollard, and will live and be productive, in this state, for a great number of years. When grown exclusively for the timber of its trunk, however, it requires to be allowed a considerable amplitude of head; perhaps not less than one third of its whole height. The timber, in this case, is found to be far inore compact and durable, though not so curiously veined and variously coloured, as it is when the tree is allowed to produce branches from the ground upwards. The timber of the elm, not being remarkable for its durability, is, in old trees, very
commonly found decayed at the heart; and this is very generally the case, even when the exterior circumference of the trunk' is in a healthy and vigorous state, and prolific of branches. The most profitable age for felling the elm is between 70 and 80 years; and, if the trunk is disbarked a year before it is cut down, the wood will be more thoroughly seasoned.
Accidents, Diseases, and Insects. The elm is not a brittle tree; and, from the straightness and strength of its trunk in proportion to its head, it is not liable to be injured by high winds. is, however, subject to many diseases ; and is very liable to be attacked by insects. The principal disease with which it is assailed is, a species of ulceration, “ which appears on the body of the tree, at the height of 3 ft. or 4 ft. from the ground, and which discharges a great quantity of sap. The disease penetrates gradually into the interior of the tree, and corrupts its substance. Many attempts have been made to cure it in the beginning, or to arrest its progress, but hitherto without success. The best treatment is to pierce the tree to the depth of 2 in. or 3. in. with an auger, in the very heart of the malady, which is declared by the flowing of the sap.” (Michr.) The matter discharged by this ulcer has been analysed by M. Vauquelin, and found to contain 0340 parts of carbonate and sulphate of potash; 0·051 of carbonate of lime; and 1-004 parts of carbonate of magnesia. (Mém. de l'Institut, tom. ii.) The mode of treatinent reconimended in the Nouveau Cours d'Agriculture is, to pierce the ulcer, as above advised by Michaux, and then to dress the wound with powdered charcoal, or a mixture of cow-dung and clay. Elms, when in a soil which does not suit them (viz. when it is either excessively wet, or excessively dry), are very subject to a disease called carcinoma. “An unusual deposit of cambium takes place between the wood and the bark : no new wood is formed, but, instead of it, the cambium becomes putrid, and oozes out through the bark, which thus separates from the albumen." (Lindl. Introd. to Bot., p. 298.) This disease shows itself by the extravasated cambium forming long black streaks down the bark, and by its sweetness attracting numerous insects, of several tribes, to prey upon it. Mr. Spence thinks that this disease is very probably caused by the scolyti. “I have seen,” he says, “many elms pierced by these insects, where the extravasated cambium partly oozed out in white masses like gum or manna, and partly formed long black streaks down the bark (as described above), and numerous insects were attracted to feed on it.”
Many kinds of insects attack the elm. One of these, a species of Háltica (vulgarly called the elm flea, from its habit of leaping), devours the leaves, but is said not to do any serious injury to the tree. (See Ent. Mag., i. p. 427.) It is a beautiful little insect, covered with a brilliant cuirass of gold, and having the thighs of its hinder legs so large as to appear almost round. These insects are so lively, and so quick in their movements, that, though a branch may appear covered with them one moment, the next they have all vanished. The larvæ are small and slender, and devour the leaves equally with the perfect insect. (See Dict. Classique d'Hist. Nat., art. Altise; and Nouv. Cours d'Agric., tom. i. p. 256.) in the Dictionnaire des Eaux et Forêts, and in the Nouveau Du Hamel
, it is mentioned that galls, or small bladders, are produced on the leaves of the elm, by the puncture of some kind of insect (probably some species of Cynips), which are first green, but afterwards turn black. These galls each contain some drops of a liquid, which is called, according to Du Hamel, elm balm, and was formerly employed for the cure of recent wounds. In the Nouveau Cours d'Agriculture, four insects that feed on the elm are mentioned. The first is the common caterpillar Bómbyx chrysorrhæ'a Fab., which destroys the leaf buds and leaves entirely, so as to give the tree, in spring, the appearance of winter. The second is the galeruque de l'orme (Galerùca ulmariénsis Fab.), a coleopterous insect, the larvæ of which, in some seasons, entirely destroy the leaves of the elm trees in the public promenades both in England and on the Continent. Mr. Spence mentions that, visiting the boulevards at Rouen, in the summer of 1836, he found the larvæ of this insect had so completely destroyed the leaves of the
elms planted there, by eating the parenchyma, and leaving the skeleton of the leaves dry and brown, that, at first sight, he supposed they had all been blighted by some neighbouring manufactory of acid. These larvæ are blackish, and exhale, when crushed, a most disagreeable smell. They coil up the moment they are touched, and let themselves fall to the ground. The perfect insect is extremely sluggish in its movements, counterfeiting death, in cases of danger, rather than unfolding its wings to fly away. (See Dict. Classique d'Hist. Nat., art. Galeruque.) It conceals itself in the interstices of the bark, under stones, and between the bricks of walls ; and will produce, sometimes, three generations in the course of one summer. The third is a species of Cóssus (Cóssus Ligniperda Fab.), or Goat Moth (fig. 1233.), which has destroyed
innumerable trees, particularly in the neighbourhood of Paris. The larva (fig. 1233. a) is about 3 in. long, with its body sprinkled with slender hairs ; it is of a reddish brown on the back, becoming yellow beneath, with eight breathing-holes on the sides, and a black head. It exhales a most disagreeable odour, which is produced by an oily and very acrid liquor, which it discharges from its mouth; and the use of which is supposed to be to soften the wood before it devours it. This liquor has a strong scent, like that of a goat, whence the English name of the insect is derived. The pupa (c) is brown, the abdominal