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same; slight crops of potatoes with short tops, or turnips, may be admitted into such plantations with advantage for two or three years, as they create a necessity for annually digging or stirring the surface, and tend very materially to accelerate the growth of the plants. It may be objected, that such crops must impoverish the soil, and no doubt such is the fact, so far as common vegetables are concerned: but as to the production of wood, its support depends, in a great measure, on a different species of nutriment; and hence, I could never observe, that such cropping damaged it materially." (Profit. Plant. p. 153.)

3982. Osier plantations, for baskets, willows, and hoops, require digging and cleaning during the whole course of their existence; and so do hedgerows to a certain extent, and some ornamental plantations.

SUBSECT. 3. Filling up of Blanks or Failures in Plantations.

3983. The filling up of blanks is one of the first operations that occurs on the culture of plantations, next to the general culture of the soil, and the care of the external fences. According to Sang, "a forest plantation, either in the mass form or ordinary mixture, should remain several years after planting, before filling up the vacancies, by the death of the hard-wood plants, takes place. Hard-wood plants, in the first year, and even sometimes in the second year, after planting, die down quite to the surface of the ground, and are apparently dead, while their roots, and the wood immediately above them, are quite fresh, and capable of producing very vigorous shoots, which they frequently do produce, if allowed to stand in their places. If a tree, such as that above alluded to, be taken out the first or second year after planting, and the place filled up with a fresh plant of the same kind, what happened to the former may probably happen to the latter; and so the period of raising a plant on the spot may be protracted to a great length of time; or it is possible this object may never be gained.

3984. The filling up of the hard-wood kinds in a plantation which has been planted after trenching or summer fallow, and which has been kept clean by the hoe, may be done with safety at an earlier period than under the foregoing circumstances; because the trees, in the present case, have greater encouragement to grow vigorously after planting, and may be more casily ascertained to be entirely dead, than where the natural herbage is allowed to grow among them.

3985. But the filling up of larches and pines may take place the first spring after the plantation has been made; because such of these trees as have died are more easily distinguished. In many cases where a larch or pine loses its top, either by dying down, or the biting of hares or rabbits, the most vigorous lateral branch is elected by nature to supply the deficiency, which by degrees assumes the character of an original top. Pines, and larches, therefore, which have fresh lateral branches, are not to be displaced, although they have lost their tops. Indeed, no tree in the forest, or other plantation, ought to be removed until there be no hope of its recovery.

3986. If the filling up of plantations be left undone till the trees have risen to fifteen or twenty feet in height, their roots are spread far abroad, and their tops occupy a considerable space. The introduction of two or three plants, from a foot to three feet in height, at a particular deficient place, can never, in the above circumstances, be attended with any advantage. Such plants may, indeed, become bushes, and may answer well enough in the character of underwood, but they will for ever remain unfit for any other purpose. It is highly improper then, to commence filling up hard-wood plantations before the third year after planting; or to protract it beyond the fifth or the sixth. March is the proper season for this operation. (Plant. Kal. 295.)

SUBSECT. 4. Pruning and Heading down Trees in Plantations.

3987. Pruning is the most important operation of tree culture, since on it, in almost every case, depends the ultimate value, and in most cases the actual bulk, of timber produced. For pruning, as for most other practical purposes, the division of trees into resinous or frondose-branched trees, and into non-resinous or branchy-headed sorts, is of use. The main object in pruning frondose-branched trees is to produce a trunk with clean bark and sound timber; that in pruning branchy-stemmed trees is principally to direct the ligneous matter of the tree into the main stem or trunk, and also to produce a clean stem and sound timber, as in the other case. The branches of frondose trees, unless in extraordinary cases, never acquire a timber size, but rot off from the bottom upwards, as the tree advances in height and age; and, therefore, whether pruned or not, the quantity of timber in the form of trunk is the same. The branches of the other division of trees, however, when left to spread out on every side, often acquire a timber-like size; and as the ligneous matter they contain is in general far from being so valuable as when produced in the form of a straight stem, the loss by not pruning off their side branches or preventing them from acquiring a timber-like size is evident. On the other hand, when they are broken off by accident, or rot off by being crowded together, the

timber of the trunk, though in these cases increased in quantity, is rendered knotty and rotten in quality.

3988. Pruning frondose or resinous trees is one of the greatest errors in the modern system of forest management. The branches of the different species of pines, and of the cedar of Lebanon, never attain a timber size, if growing in a moderately thick plantation; those of the fir tribe never under any circumstances. Provided pines and cedars, therefore, are planted moderately thick, no loss in point of timber can ever be sustained by omitting altogether to prune them; and in this respect the fir tribe, whether thick or thin on the ground, may be left to themselves. The important question is, how does the rotting off of the branches affect the timber in the trunk of the tree? Certainly no pine or fir timber can be sounder or better than that which is brought from the native forests of the north of Europe, and from America, where no pruning is ever given. The rotting off of the frondose branches, therefore, cannot be injurious in these countries. The next question is, can it be proved to be injurious in this country? We are not aware that it has, and do not believe that it can. The rotting off of the branch of a resinous tree is a very different process from the rotting off of a branch of a ramose-headed tree. This fact may be verified by observing what takes place in pine or fir woods, and by inspecting the interior of foreign pine or fir, cut up into planks. In the rotting off of side branches of deciduous trees, we find, that the principal part where decay operates, at least in all the soft woods, and even in the oak when it is young, is the heart; but in the rotting off of the side branches of resinous trees, we shall find them decaying chiefly on the outside, and wearing down the stump of the fallen branch in the form of a cone. On examining the sections of sound foreign deal, we shall find that the knots of the side branches always terminate in cones when the section is made vertically. This is a fact well known to every carpenter; and it is also known to a great many, that British pine and fir timber that has been pruned, has invariably a rotten space at every knot. The same thing is observable to a certain extent in the natural decay of the side branches of all trees. When the decay is natural, it commences at the circumference, and wears down the stump, till it ends in a small hard cone, which is buried in the increasing circumference of the tree, and is never found injurious to the timber: when the decay is artificial, or in consequence of excessive pruning, that is, suddenly exposing a large section to the action of the atmosphere, the bark protects the circumference, and the decay goes on in the centre, so as to end in forming an inverted cone of rotten matter, which serves as a funnel to conduct moisture to the trunk, and thereby render it rotten also. The conclusion which we draw from these facts is, that the pine and fir tribe should scarcely be pruned at all, and that no branches of ramose trees should be cut off close to the stem of a larger size than what may be healed over in one or at most two seasons. We agree with Cruickshank, therefore, when he says, "It would appear that the pruning of firs [the pine and fir tribe], supposing it harmless, can yet be productive of no positive good."

3989. Cruickshank, Pontey, and Sang, agree that the great object of pruning is to protect the leader or main stem or shoot from the rivalship of the side branches, in order that as much of the nourishment drawn from the soil may be employed in the formation of straight timber, and as little in the formation of branches and spray, as is consistent with the economy of vegetation. Without the agency of the leaves, the moisture absorbed from the soil could no more nourish a plant than the food taken into the stomach would nourish an animal without the process of digestion. The branches bearing the leaves are therefore just as necessary to the welfare of the tree as the roots. By taking away too many of the branches, only a small part of the fluid imbibed will be elaborated; by leaving the branches too thick and crowded, the leaves may be less perfect, and less fit for performing their office, than they otherwise would be. Exposure of a part of the branches to the light and air may therefore be a sufficient reason for thinning them, independently of increasing the trunk. "How," asks Cruickshank, "are we to know the exact number of branches that may be removed with safety in any given circumstances? Never, it is answered, displace any which have not already got, or seem in immediate danger of getting, the upper hand of the leader. These will be known by their equalling or approaching the leader in size; or, to speak less ambiguously, by their being of the same, or nearly of the same, girth at the place where they spring from the stem, as the stem itself is at their length from its top." In proceeding according to this plan, the pruner is not to regard, in the smallest degree, the part of the stem on which a shoot is situated. If it is too large, it must be displaced, should it be in the highest part of the tree: if it is not too large, it must remain, though it be close to the ground.

"But how will this method, the reader may be ready to ask, ever produce a clean stem? By repeating the pruning, it is answered, as often as the growth of the branches may make the operation necessary. Suppose, the first time a tree undergoes the process, that the branches removed are a considerable distance from the ground, and that there are several smaller ones left growing farther down the stem: these last will gradually increase in size, till they, too, must be lopped off, and thus the stem will be in the end as effectually cleared, though more gradually, and consistently with the health of the tree, as by the absurd method represented above.

"If any branches that were left at a former pruning low on the stem, appear at the next repetition of the process not to have increased in size, we may safely conclude that they have had no influence on the tree either good or bad; and as it would be in vain to leave them with the hope that they will any longer assist in the elaboration of the sap, they should be removed, as unsightly objects which it is no longer useful to preserve." (Practical Planter, p. 168.)

3990. Billington considers the leaves and branches of trees as of the greatest importance: he thinks every timber tree ought to have the trunk clothed with branches throughout; but these branches he would shorten in such a way that they should never engross any material part of the timber of the tree. To accomplish this, it is necessary to commence pruning when the trees are young, by which means the great bulk of the timber produced will be deposited in the main stem or trunk. This is what he calls

Holkham, under the name of foreshortening, and is advocated by Sir Henry Steuart, under that of termina! pruning.

3991. Most erroneous opinions on the subject of pruning resinous trees have been propagated by Salmon, the experienced manager of the late Duke of Bedford, Pontey, forestpruner to the same duke, and others of less note. Sang, on the other hand, argues against excessive pruning of the resinous tribe of trees as injurious to the health of the tree and the soundness of its timber. Elles, also, a gardener of scientific acquirements, and extensive experience in England, his native country, and in Scotland and Ireland, would never prune the pine and fir tribe at all, unless when very young, and when the side shoots could be pinched off with the finger and the thumb. At a more advanced age, if compelled by circumstances to prune, he would only shorten' the extremities of the fronds. Of two trees, pines, firs, cedars, or larches, the one pruned and the other unpruned, there will be found, he says, most timber in the trunk of the unpruned one, while the branches are so much in addition to the value of the tree. He excepts, of course, those cases in which frondose branches take a ramose character, in consequence of the tree standing alone, as is frequently the case with the cedar of Lebanon, and sometimes with the Scotch pine.

3992. Our own opinion with respect to pruning the resinous trees is in accord with that of Elles and Cruickshank; and as to hard and soft wooded leaf trees, we think Cruickshank's practice and rule unexceptionable. We would prune the last description of trees much less than is generally done, and leave the pine and fir tribe in a great measure to nature, taking care, however, to thin betimes and occasionally from infancy till the maturity of the trees. We have no doubt of this, that when the larch and Scotch pine trees planted in the end of the last century, and severely pruned for the first twenty or twenty-five years of the present, shall come to be cut down and sawn up, their timber will be found full of faults, and of very little value, compared with timber of the same sorts from natural and unpruned woods, foreign and domestic.

3993. With respect to the manner of pruning, Sang observes, "Where straight timber is the object, both classes in their infancy should be feathered from the bottom upwards,

C

594

b

keeping the tops light and spiral, something resembling a young larch (fig. 594. a). The proportion of their tops should be gradually diminished, year by year, till about their twentieth year, when they should occupy about a third part of the height of the plant; that is, if the tree be thirty feet high, the top should be ten feet (b). In all cases in pruning off the branches, the utmost care must be taken not to leave any stumps sticking out, but cut them into the quick. It is only by this means that clean timber can be procured for the joiner; or slightly stemmed trees to please the eye. It is a very general practice to leave snags or stumps (c): before the bole can be enlarged sufficiently to cover these, many years must elapse; the stumps in the mean time become rotten; and the consequence is, timber which, when sawn up (d), is only fit for fuel."

3994. The general seasons of pruning are winter and spring, and for the gean or wild cherry midsummer, as it is found to gum very much at any other season. Pontey says, "As to the proper seasons of pruning, there is only one difficulty; and that is, discovering the wrong one, or the particular time that trees will bleed. Only two trees have been found which bleed uniformly at certain seasons, namely, the sycamore and fir, which bleed as soon as the sap begins to move." There is, however, one season for pruning unquestionably preferable to all others, as far as the welfare of the tree, and the soundness of its future timber, is concerned. It is well known to physiologists and observing gardeners, that when the sap is returning, wounds heal with the greatest rapidity. Hence, in all plants which are difficult to strike from cuttings, the gardener makes choice of the point of a shoot in that particular stage of maturation when the sap is returning; that is, when the base of the shoot is beginning to assume a ligneous character. This, in hardy trees, is uniformly a week or a fortnight after midsummer, and it will be found that the wounds made by cutting off branches at that season, or any time within three weeks after midsummer, will, in the course of four or five weeks, be partly covered with a callosity proceeding from the lips of the wound. Wounds made by cutting branches off the same trees, five weeks after midsummer, will remain without the slightest indi

cation of healing at the edges till the following spring; and if the tree is delicate, or the winter severe, they will then be in a worse condition than if they had not been pruned at all; the lips of the wounds will have begun to decay. The only seeming contradiction to this general law in trees is where what are called second growths are produced, as in the oak and some other trees, and in such cases there is of course a second returning sap, for the same reason that there was at first. (Gard. Mag. vol. vi. p. 94.)

3995. In spring pruning, desist when bleeding takes place. As a general rule, Pontey thinks "summer preferable to winter pruning; because, in proportion as wounds are made early they heal so much more in the same season." (Forest Pruner, 236.) Sang suspends pruning from the end of February to the middle of July, but carries it on during every other month of the year; pruning the wild cherry, or any other tree very apt to gum, only in July and August. (Plant. Kal. 268.)

3996. With respect to the implements to be used, Sang observes, "In every case where the knife is capable of lopping off the branch in question, namely, in the pruning of infant plants, it is the only instrument necessary. All other branches should be taken off by the saw. A hatchet, or a chisel, should never be used. Every wound on the stem or bole should be quite into the quick, that is, to the level and depth of the bark; nor should the least protuberance be left. The branch to be lopped off by the saw should, in all cases, be notched or slightly cut on the under side, in order to prevent the bark from being torn in the fall; and when the branch has been removed, the edges of the wound, if anywise ragged, should be pared smooth with the knife. If the tree be vigorous, nature will soon cover the wound with the bark, without the addition of any plaster to exclude the air. In the shortening of a strong branch, the position of which is pretty upright, it should be observed to draw the saw obliquely across it, in such a manner as that the face of the wound shall be incapable of retaining moisture; and afterwards to smooth the edges of the bark with a knife." (Plant. Kal. 181.) In every case where the branches are too large for the knife, Pontey prefers the saw, as the best and most expeditious instrument; and one, the use of which is more easily acquired by a labourer than that of either the bill or axe. In "large work" he uses the common carpenter's saw; for smaller branches, one with somewhat finer teeth, with the plate of steel, about twenty inches long.

3997. The pruning of all deciduous trees should be begun at the top, or at least those branches which are to be removed thence should never be lost sight of "Having fixed upon what may be deemed the best shoot for a leader, or that by which the stem is most evidently to be elongated and enlarged, every other branch on the plant should be rendered subservient to it, either by removing them instantly, or by shortening them. Where a plant has branched into two or more rival stems, and there are no other very strong branches upon it, nothing more is required than simply to lop off the weakest clean by the bole, leaving only the strongest and most promising shoot. If three or four shoots or branches be contending for the ascendency, they should, in like manner, be lopped off, leaving only the most promising. If any of the branches which have been left farther down on the bole of the plant at former prunings have become very strong, or have extended their extremities far, they should either be taken clean off by the bole, or be shortened at a proper distance from it, observing always to shorten at a lateral twig of considerable length. It is of importance that the tree be equally poised; and, therefore, if it have stronger branches on the one side than on the other, they should either be removed or be shortened. Thus, a properly trained tree, under twenty feet in height, should appear light and spiral, from within a yard or two of the ground to the upper extremity, its stem being furnished with a moderate number of twigs and small branches, in order to detain the sap, and circulate it more equally through the plant.

3998. The subsequent prunings of trees of this size, standing in a close plantation, will require much less attention; all that is wanted will consist in keeping their leading shoots single. From the want of air, their lateral branches will not be allowed to extend, but will remain as twigs upon the stem. These, however, frequently become dead branches; and if such were allowed to remain at all on the trees, they would infallibly produce blemishes calculated greatly to diminish the value of the timber: hence the im propriety of allowing any branch to die on the bole of a tree; indeed, all branches should be removed when they are alive; such a method, to our knowledge, being the only sure one to make good timber. From these circumstances, an annual pruning, or at least an annual examination, of all forests is necessary. (Plant. Kal.)

3099. Heading down such non-resinous trees as stole, we have already stated to be an important operation. After the trees have been three or four years planted, Sang directs, that "such as have not begun to grow freely should be headed down to within three or four inches of the ground. The cut must be made with the pruning-knife in a sloping direction, with one effort. Great care should be taken not to bend over the tree in the act of cutting. By so bending, the root may be split, a thing which too often happens. The operation should be performed in March, and not at an earlier period of the season, because the wounded part might receive much injury from the severe weather in January and February, and the expected shoot be thereby prevented from rising so strong and vigorous." (Plant. Kal. 297.) Buffon, in a Memorial on the Culture of Woods, presented to the French government in 1742, says he has repeated this experiment so often, that he considers it as the most useful practice he knows in the culture of woods.

4000. For the purpose of producing bends for ship-timber, various modes of pruning have been proposed, as such bends always fetch the highest price. According to Pontey, "little is hazarded by saying, that if plenty of long, clean, straight, free-grown trees could be got, steaming and a screw apparatus would form bends."

4001. Monteith, a timber valuator of great experience, and in extensive practice, says, the value of the oak, the broad-leaved elm, and Spanish chestnut, depends a good deal on their being crooked, as they are all used in ship building. He says he has seen trees successfully trained into crooked shapes of great value, in the following manner:-"If you have an oak, elm, or chestnut, that has two stems, as it were, striving for the superiority, lop or prune off the straightest stem; and if a tree that is not likely to be of such value be standing on that side to which the stem left seems to incline to a horizontal position, take away the tree, and thus give the other every chance of growing horizontally. At this time it will be necessary to take away a few of the perpendicular shoots off the horizontal branch; and, indeed, if these branches, which is sometimes the case in such trees, seem to contend, take away most of them; but if they do not, it is better at this time not to prune over much, except the crooked shoots on the horizontal branch, till they arrive at the height of fifteen or even twenty feet. By this time it will be easily seen

what kind of tree it is likely to form; and, if it inclines to grow crooked, lighten a little the top of the tree, by taking off a few of the crooked branches on the straighter side, allowing all the branches to remain on the side to which the tree inclines to crook, to give it more weight, and to draw most of the juice or sap that way, and it will naturally incline more to the crook; at the same time clearing away any other tree on the crooked side, that may be apt, with the wind, to whip the side of the tree to which it inclines to crook. Also taking away such trees of less value as may prevent it from spreading out to the one side more than to the other." He adds, "I have myself tried the experiment with several oak trees at about twelve feet high, that were a little inclined to crook, and that had also a main branch inclined to a horizontal position. In the course of less than twenty years, I had the pleasure of seeing some of these very trees grow so very crooked that the branch would work in with the main stem or body of the tree, to a complete knee or square, which is the most valuable of all trees; and, as ten trees of crooked oak aré required for one straight one, it is of the most essential consequence to have crooked oak trees; and, besides, an oak tree, properly crooked, that will answer for a large knee (say the main branch, to be fit to work in with the body or trunk of the tree without much waste of wood), is nearly double in value to the same number of feet of a straight tree; and, indeed, knees of oak are extremely scarce, and difficult to be got." 4002. Pontey "knows of no way by which bends of tolerable scantlings (knees excepted) can be produced with certainty and little trouble, but from a side branch kept in a bent position by the branches of another tree or trees overhanging its stem." (Forest Pruner, 174.)

4003. Coppice woods, in so far as grown from poles or bark, require pruning on the same principle as timber trees, in order to modify the ligneous matter into stem, and produce clean bark. In as far as they are grown for fence wood, fuel, or besom spray, no pruning is required.

4004. Osier holts require the laterals to be pinched off the shoots intended for hoops; those of the basket-maker seldom produce any. The stools, also, require to be kept free from dead wood, and stinted knotted protuberances.

4005. Hedges require side pruning, or switching, from their first planting, so as gradually to mould them into "the wedge shape, tapering from bottom to top on both sides equally, till they meet in a point at the top. Two feet at bottom is a sufficient breadth for a five feet hedge; a greater or less height should have the bottom wider or narrower, accordingly. In dressing young hedges, either of the deciduous or evergreen kinds, the sides only should be cut till the hedge arrives at the proposed height, unless it be necessary, for the sake of shelter, to cut their tops over, in order to make the hedges thicker of branches. Such cutting of the upright shoots, however, is not of any great use in this respect; because every hawthorn hedge sends out a number of side shoots, which, if encouraged, by keeping the top wedge-shaped as above, will make it abundantly thick." (Sang, 447.) In pruning hedges, some use shears; but the hedgebill is the most proper instrument, producing a smooth unfractured section, not so apt to throw out a number of small useless shoots which generally follow the crushing cut of the sheers.

4006. Hedge-row trees require to be pruned to a tall, clean, erect stem, as at once producing more timber, and doing least injury to the ground under their drip and shade.

4007. Trees in strips for shelter, or screens for concealment, ought to be furnished with branches, from the bottom upwards; unless undergrowth supply this deficiency. Where this is not the case, care should be had that the trees be pruned into conical shapes, so as that the lower branches may be as little as possible excluded from the influence of the weather by the upper ones.

4008. Trees for shade, where shelter from winds is not wanting, should be pruned to ample spreading heads with naked stems; the stem should be of such a height that the sun's rays, at midday, in midsummer, may not fall within some yards of the base of the trunk; thus leaving under the trees, as well as on their shady side, a space for the repose of men or cattle.

SUBSECT. 5. Thinning young Plantations.

4009. The properly thinning out of plantations, Sang observes, "is a matter of the first importance in their culture. However much attention be paid to the article of pruning, if the plantation be left too thick, it will be inevitably ruined. A circulation of air, neither too great nor too small, is essential to the welfare of the whole. This should not be wanting at any period of the growth of the plantation; but in cases where it has been prevented by neglect, it should not be admitted all at once, or suddenly. Opening a plantation too much at once, is a sure way to destroy its health and vigour. In thinning, the consideration which should, in all cases predominate, is to cut for the good of the timber left, disregarding the value of the thinnings. For, if we have it in our choice to leave a good, and take away a bad plant or kind, and if it be necessary that one of the two should fall, the only question should be, by leaving which of them shall we do most justice to the laudable intention of raising excellent and full-sized timber for the benefit of ourselves and of posterity? The worst tree should never be left, but with the view of filling up an accidental vacancy."

4010. Salmon, from observations on the most orderly and thriving plantations at Woburn, deduces the following rule for thinning: -"Keep the distance of the trees from each other equal to one-fifth of their height. In the application of this rule for thinning, it is evident that each individual tree can never be nade to comply; for the original distance (even if planted in the most regular order) will allow only of

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