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of ourselves and of posterity? The worst tree should never be left, but with the view of filling up an accidental vacancy.

3710. In thinning mixed plantations, the removing of the nurses is the first object which generally claims attention. This however should be cautiously performed; otherwise the intention of nursing might, after all, be thwarted. If the situation be much exposed, it will be prudent to retain more nurses, although the plantation itself be rather 'crowded, than where the situation is sheltered. In no cases, however, should the nurses be suffered to overtop or whip the plants intended for a timber crop; and for this reason, in bleak situations, and when perhaps particular nurse plants can hardly be spared, it may be sometimes necessary to prune off the branches from one side entirely. At subsequent thinnings, such pruned or disfigured plants are first to be removed; and then those which, from their situation, may best be dispensed with.

3711. At what period of the age of the plantation the nurses are to be removed, cannot easily be determined; and, indeed, if the nurses chiefly consist of larches, it may with propriety be said, that they should never be totally removed, while any of the other kinds remain. For, besides that this plant is admirably calculated to compose part of a beautiful mixture, it is excelled by few kinds, perhaps, by none as a timber tree.

3712. But when the nurses consist of inferior kinds, such as the mountain ash or Scots pine, they should generally be all moved by the time the plantation arrives at the height of fifteen or twenty feet, in order that the timber trees may not, by their means, be drawn up too weak and slender. Before this time it may probably be necessary to thin out a part of the other kinds. The least valuable, and the least thriving plants, should first be condemned, provided their removal occasion no blank or chasm; but where this would happen, they should be allowed to stand till the next, or other subsequent revision. 3713. At what distance of time this revision should take place, cannot easily be determined; as the matter must very much depend on the circumstances of soil, shelter, and the state of health the plants may be in. In general the third season after will be soon enough; and if the plantation be from thirty to forty years old, and in a thriving state, it will require to be revised again, in most cases within seven years. But one invariable rule ought to prevail in all cases, and in all situations, to allow no plant to overtop or whip another. Respect should be had to the distance of the tops, not to the distance of the roots of the trees; for some kinds require more head room than others; and all trees do not rise perpendicular to their roots, even on the most level or sheltered ground.

3714. With respect to the final distance to which trees, standing in a mixed plantation, should be thinned, it is hardly possible to prescribe fixed rules; circumstances of health, vigor, the spreading nature of the tree, and the like, must determine. Whether the trees are to be suffered to stand till full grown; which of the kinds the soil seems best fitted for ; whether the ground be flat or elevated; and whether the situation be exposed or sheltered, are all circumstances which must influence the determination of the ultimate distance at which the trees are to stand. It may, however, be said in general, that if trees be allowed a certain distance of from twenty five to thirty feet, according to their kinds and manner of growth, they will have room to become larger timber.

3715. Plantations of Scots pine, if the plants have been put in at three, or three and a half feet apart, will require little care until the trees be ten or twelve feet high. It is necessary to keep such plantations thick in the early part of their growth, in order that the trees may tower the faster, and push fewer and weaker side branches. Indeed, a pine or soft-wood plantation should be kept thicker at any period of its growth, than any of those consisting of hard-wood and nurses already mentioned; and it may sometimes be proper to prune up certain plants as nurses, as hinted at above for nurses in a mixed plantation. Those pruned-up trees are of course to be reckoned temporary plants, and are afterwards to be the first thinned out; next to these, all plants which have lost their leaders by accident, should be condemned; because such will never regain them so far, as after to become stately timber; provided that the removal of these mutilated trees cause no material blank in the plantation. Care should be taken to prevent whipping; nor should the plantation be thinned too much at one time, lest havock be made by prevailing winds; an evil which many, through inadvertency, have thus incurred. This precaution seems the more necessary, inasmuch as Scots pines, intended for useful large timber, are presumed never to be planted except in exposed situations and thin soils. At forty years of age, a good medium distance for the trees may be about fifteen feet every way. It may be worthy of remark, that after a certain period, perhaps by the time that the plantation arrives at the age of fifty or sixty years, it will be proper to thin more freely, in order to harden the timber; and that then this may be done with less risk of danger, from the strength the trees will have acquired, than at an earlier period; but still it should be done gradually.

3716. Plantations of spruce and silver firs, intended for large useful timber, should be kept much in the manner above stated, both in their infancy and middle age.

As

already remarked, planting and keeping them as thick as is consistent with their health, is the best means of producing tall, straight, clean stems, and valuable timber. When planted for screens or for ornament, they require a different treatment; which will be noticed in the proper place. "To larch plantations, the above observations will also apply, and indeed they are applicable to plantations of all kinds of resinous trees. It may be proper here to remark, that the exposed margin of all young plantations should be kept thicker than the interior. The extent to which this rule should be carried, must be regulated according to the degree of exposure of the situation, the age of the plants, the tenderness of the kinds, and other circumstances." Autumn, or very early in the spring, are the proper seasons for thinning where the trees are to be taken up by the root and replanted elsewhere; winter for thinning for timber and fuel; but such trees as are valuable for their barks should be left untouched till the sap rises in April or May.

3717. Copse-woods require thinning when young, like other plantations, and when once established the stools require to be gone over the second year after cutting, and all superfluous suckers and shoots removed. This operation should be repeated annually, or every two or three years, in connection with pruning, till within three or four years of the general fall of the crop.

SECT. VI. Of the Improvement of Neglected Plantations.

3718. Neglected and mismanaged plantations will include the greater number in Britain. The artificial strips and masses have generally never been thinned or pruned; and the natural wood or copse-woods improperly thinned or cut over. It is often a difficult matter to know what to make of such cases, and always a work of considerable time. "Trees," Sang observes, "however hardy their natures may be, which have been reared in a thick plantation, and consequently have been very much sheltered, have their natures so far changed, that if they be suddenly exposed to a circulation of air, which, under different circumstances, would have been salubrious and useful to them, will become sickly and die. Hence the necessity of admitting the air to circulate freely among trees in a thick plantation, only gradually, and with great caution."

3719. A plantation which has become close ond crowded, having been neglected from the time of planting till perhaps its twentieth year, should only have some of the smallest and most unsightly plants removed; one, perhaps, in every six or eight, in the first season; in the following season, a like number may be removed; and, in two or three years afterwards, it should be gone over again, and so on, till it be sufficiently thinned. It will be proper to commence the thinning, as above, at the interior of the plantations, leaving the skirts thicker till the last; indeed, the thinning of the skirts of such a plantation should be protracted to a great length of time. With thinning, pruning to a certain extent should also be carried on. "If the plantation," Sang observes, "consists of pines and firs, all the rotten stumps, decayed branches, and the like, must be cut off close by the bole. It will be needful, however, to be cautious not to inflict too many wounds upon the tree in one season; the removing of these, therefore, should be the work of two or three years, rather than endanger the health of the plantation. After the removal of these from the boles of the firs and larches, proceed every two or three years, but with a sparing hand, to displace one or perhaps two tiers of the lowermost live branches, as circumstances may direct, being careful to cut close by the trunk, as above noticed. In a plantation of hard-wood, under the above circumstances, the trees left for the ultimate crop, are not to be pruned so much at first as might otherwise be required; only one or two of their competing branches are to be taken away, and even these with caution. If it be judged too much for the first operation to remove them entirely, they may be shortened, to prevent the progress of the competition; and the remaining parts may be removed in the following season; at which time, as before observed, they must be cut close by the bole." (Plant. Kal. 467.)

3720. The operation of thinning and pruning, thickening or filling up, or renewing portions that cannot be profitably recovered, should thus go on, year after year, as appearances may direct, on the general principles of tree culture. And for this purpose,

the attentive observation and reflection of a judicious manager will be worth more than directions which must be given with so much latitude. Pontey has noticed various errors in

3721. Kennedy's Treatise on Planting, and even in Sang's Kalendar, on the simple subject of distances, which have originated in their giving directions for anticipated cases which had never come within their experience. "Most people," he says, " take it for granted, that if trees stand three feet apart, they have only to take out the half to make the distances six feet, though to do that, they must take down three times as many as they leave. By the same rule, most people would suppose that twelve feet

distance was only the double of six ; but the square of the latter is only thirty-six, while that of the former is one hundred and forty-four, or four times the latter; so that to bring six feet distances to twelve, three trees must be removed for every one left." (Profitable Planter, 256, and Forest Pruner, 21.)

458

3722. Copse-woods are sometimes improved by turning them into woods, which requires nothing more than a judicious selection and reservation of those shoots from the stools which are strongest, and which spring more immediately from the collar. But a greater improvement of copse-woods consists in cutting over the overgrown and protuberant stools by the surface of the soil (fig. 458 a, b, c, d), which has been found by Monteith completely to regenerate them. The operation is performed with a saw, in a slanting direction, and the young shoots being properly thinned and pruned, soon establish themselves securely on the circumference of large and perhaps rotten-hearted roots. (Forester's Guide, 60.) 3723. Neglected hedge-row timber may be improved by pruning according to its age.

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Blakey recommends what he calls fore-shortening, or cutting-in, as the best method both for young and old hedge-row timber. "This operation is performed by shortening the over-luxuriant sidebranches (fig. 459 a), but not to cut them to a stump, as in snagpruning; on the contrary, the extremity only of the branch should be cut off, and the amputation effected immediately above where an auxiliary side-shoot springs from the branch on which the operation

is to be performed (b); this may be at the distance of two, four, or any other number of feet from the stem of the tree; and suppose the auxiliary branch which is left (when the top of the branch is cut off) is also over-luxuriant, or looks unsightly, it should also be shortened at its sub-auxiliary branch, in the same manner as before described. The branches of trees, pruned in this manner, are always kept within due bounds; they do not extend over the adjoining land to the injury of the occupier, at least not until the stem of the tree rises to a height (out of the reach of pruning), when the top-branches can do comparatively little injury to the land. By adopting this system of pruning, the bad effects of close pruning on old trees, and snag-pruning on young ones, will be avoided, the country will be ornamented, and the community at large, as well as individuals, benefited."

SECT. VII. Of the Treatment of Injured and Diseased Trees.

3724. With respect to wounds, bruises, casualties, and defects of trees, such small wounds as are required to be made by judicious pruning, easily heal up of themselves; large wounds, by amputation of branches above six inches diameter, should, if possible, never be made. Even wounds of six inches diameter or under will heal quicker by the application of any material that excludes the air and preserves the wood from corruption; and we agree with Sang in recommending coal-tar, or the liquor produced from coals in manufacturing gas. It is, however, less favorable to the progress of the bark over the wound than a coating of clay or cow-dung covered with moss to keep it moist. Pontey recommends putty and two coats of paint over it. In case the wood, at a bruised or amputated place, has by neglect become already corrupted, the rotten or dead wood is to be pared out quite into the quick, and the wound is then to be dressed with tar or clay, covered with a piece of mat, sacking, or moss. A wound, hollowed out as above, may at first appear an unsightly blemish; but, in subsequent years, nature will lay the coats of wood under the new-formed bark thicker at that place; and probably may, in time, fill it up to be even with the general surface of the tree.

3725. All fractures, by whatever means produced, are to be managed as the circumstances of the case require. If a large branch be broken over at the middle of its length, it should be sawn clear off close by the lateral which is nearest to the bole of the tree: but, if there is no lateral, or branch, capable to carry forward the growth, cut the main or fractured branch in quite to the bole. In both cases, treat the wound as above recom. mended.

3726. Interior rotting, arising from the dampness of the soil, cannot by the art of man be cured; though it might have been prevented by timous draining. The hearts of trees frequently rot, where there is no excess of moisture, and especially such as have been produced from old roots left in the ground by a previous felling. Such roots when in good ground, send up very great shoots, with few leaves in proportion to their sizes; by the absence of a profusion of these, properly to concoct the juices so abundantly supplied by the roots, the fibre of the wood is loose and imperfect; the next season will produce more leaves in proportion to the supply of juices, yet not a sufficient number for making timber; several years may pass before this event will arrive: thus crude and ill-digested timber disposed to premature decay is the foundation over which subsequent coatings of wood are laid: yet, however perfect these may be, they do not prevent the progress of decomposition going on in the interior. Nature teaches how necessary numerous leaves are to the proportion of the solid wood; the cotyledons and subsequent leaves of a oneyear old tree, are a thousand times greater, compared to its solid contents, than are leaves to the solid contents of the first year's shoots from roots like the above.

3727. Shakes often arise from the weight and multiplicity of top branches, and might have been prevented by timous pruning. Shakes or rents in the boles of trees, however, often happen where there is no excess of tops. Sometimes the rain running down from the branches, wets one part of the bole, while the rest is comparatively dry. If this circumstance is succeeded by an intense frost, before the wetted side become dry, the bole may be rent for a length, and perhaps to the depth of the core. Shakes or rents, like the above, are difficult to cure. The best method of helping them, is to trace out their upper extremity, caulk it up with oakum, and pitch it over, to prevent the rain descending that way in future. (Sang.)

3728. In cases of hollowness, Pontey recommends probing to the bottom, letting out the water, if any, with an auger, drying the cavity with a cloth, filling it with dry sand, plugging it with wood and oakum, and then painting it over.

3729. Decorticated stems or branches by lightning, or otherwise, if the soft wood is not much injured, will heal over and become covered with bark; and this the more certainly and rapidly if the air be excluded by a coating of adhesive matter, as cow dung and quick lime, or tying on moss or bandages of mat or cloth. Pontey gives an instance in which such treatment was successful in the case of an apple tree. (Pruner, 230.) We have witnessed it on an extensive scale on the trunk of a pear tree; and we are informed, on the best authority, of other cases now under progress, in the government garden of the Luxemberg, at Paris.

3730. Withered or decayed tops, may arise from age and incipient decay; but also, as Pontey states, from improper pruning, or the want of it. We often see it from improper pruning elms, which, after having been close pruned to their summits for many years, are left entirely to nature; in that case they branch out luxuriantly below, and the top withers. By neglecting to thin out the branches on the stems of non-resinous trees the same effect may be produced.

3731. Stinted bushy tops on very tall nåked stems, show a deficiency of nourishment, from these circumstances; and on short stems from defects of the soil. Obliquely placed misshapen heads, in detached trees, commonly proceed from the same causes and want of shelter. Stinted growth, both in tops and stems, is also produced by ivy, and by lichens, mosses, miseltoe, and other parasites. Ivy compresses the bark, precludes its expansion, as well as excludes air and moisture, by which the outer bark becomes rigid and corky. Happily, both men and trees will live a long time under the influence both of deformity and disease.

3732. Excessive exudations of gum and resins are peculiar to resinous and some other trees when over pruned, or pruned at improper times. Mildew, honeydew, and blight; three popular names applied to the effects of certain insects of the aphis kind, attack the oak, beech, poplar, and many trees; all that can be said is, if proper regimen has been regularly attended to, trees will overcome these and all other enemies.

3733. Insects and vermin. Almost every tree has its particular insect of the hemipterous and dipterous families, and many of the coleoptera are common to all. The foliage of the small leaved elm of hedges is often almost entirely destroyed in the early part of the season by tenthredinidæ; and those of the larch and Scotch pine have suffered materially in some seasons from aphides. The aphis laricea, L. (Eriosomata, of Leach,) increased to an alarming extent from 1800 to 1802, on the larch, on account of three dry seasons following each other; but, though it retarded their growth, it ultimately destroyed very few trees. Sang says, he has known it since 1785; that it dirties more than injures the tree, and is now (1819) thought little of. Indeed, almost every species of tree has been known to have suffered in some one or more seasons, and in particular districts from insects; for which, on so large a scale, there seems to be no applicable remedy, but patiently waiting till their excess, or the increase of other vermin, their natural enemies,

or a change of seasons, cause them to disappear. Trees properly cultivated and managed, generally overcome such enemies. The hare is well known to be injurious to young trees, and especially to laburnums, by gnawing off their bark. Coating their stems with dung and urine, fresh from the cow-house, is said to be an effectual remedy. It may be put on with a brush to the height of two feet; a barrow load will suffice for a hundred trees, with stems of three or four inches in diameter; and its virtue, after laid on, endures at least two years. (Bull. in Cald. Hort. Mem. iv. 190.)

SECT. VIII. Of the Products of Trees and their Preparation for Use or Sale.

3734. The ordinary products of trees made use of in the arts are leaves, prunings, or spray, thinnings, seeds, flexible shoots, bark, branches, roots, and trunks. Trees also afford sap for wine and sugar, and extract for dyeing; but these products are of too accidental or refined a nature for our present purpose.

3735. The leaves and spray of trees when gathered before they begin to decay, may be given to cattle either in their fresh state or dried and stacked up for winter use, as is practised in various countries. In this country, however, leaves and spray, as the clippings of hedges and small prunings, are only used as manure; or as a substitute for tanners' bark in gardens.

3736. The thinnings, when not beyond a suitable age, and taken up properly, and at a proper season, may be planted in other situations, or as single trees and groups; or they may be used as hoops, hop-poles, poles for garden training, for fencing, for props in coaleries; and for a great variety of purposes; those, whose barks are useful for tanning, should not be cut down, or rooted up till May, but the others at any time during winter. It is common to sort them into lots, according to their kind or size; and to faggot up the spray for fuel, besom stuff, or for distilling for bleacher's liquid.

3737. The seeds of trees in general cannot be considered of much use beyond that of continuing the species. The seeds of the oak, beech, and sweet chestnut, however, are valuable for feeding swine, and where they abound may either be swept together after they drop, and carried away and preserved dry in lofts or cellars for that purpose; or if other circumstances are favorable, swine may be driven under the trees to collect them. These and other seeds, as the haw and holly, are also eaten by deer. The seeds of the trees mentioned, and of all the resinous tribe, are in general demand by the nurserymen for the purposes of propagation. The seeds of almost all other trees and shrubs are also in limited or occasional demand; or may be collected for private sowing. They generally ripen late in the season, and are to be collected in the end of autumn or beginning of winter, with the exception of a few, such as the elm, poplar, willow, and one or two others, which ripen their seeds in May and June.

The

3738. In osier grounds, willows produce flexible shoots, and whether intended for the basket-maker or cooper, should not be cut till the second season after planting, in order to strengthen the stools; but by the third autumn the crop will be fit for the basketmaker, and in the fourth, plantations intended for the cooper (hoops requiring the growth of two years) will be ready. The seasons for cutting are November and March; after the former period the wounds are apt to be injured by frost, and after the latter the sap is too far advanced; some is lost by bleeding, and the buds are developed too suddenly to admit of proper strength in the shoots. The cut should be made within three buds of the point whence the shoot issued, in a sloping direction, and the section on the underside. In cutting hoop-willows, the swell at the bottom of the shoot only should be left, that being furnished with abundance of buds for future growth. After being cut, the hoops are trimmed from any side-shoots, and tied up in bundles of a hundred, of six scores each, which, in 1820, sold for from four shillings to five shillings a bundle. willows are sorted into three sizes, and tied in bundles two feet in circumference, within a foot of the lower ends. When to be peeled, they are immediately after cutting set on their thick ends in standing water, a few inches deep, and there they remain till the sap ascends freely, which is commonly by the end of the succeeding May. "The apparatus for peeling is simply two round rods of iron, nearly half an inch thick, sixteen inches long, and tapering a little upwards, welded together at the one end which is sharpened, so as that it may be easily thrust down into the ground. When thus placed in a piece of firm ground, the peeler sits down opposite to it, and takes the willow in the right hand by the small end, and puts a foot or more of the great end into the instrument, the prongs of which he presses together with the left hand, and with the right draws the willow towards him; by which operation the bark will at once be separated from the wood: the small end is then treated in the same manner, and the peeling is completed. Good willows peeled in the above manner, have been sold for some seasons past, at from six shillings and sixpence to seven shillings the bundle of four feet in circumference. After being peeled, they will keep in good condition for a long time, till a proper market be found."

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