The author commences with some general remarks on the expediency and profit of laying uncultivated ground under timber, stating, rather too strongly, the very superior income derivable from forest than from heathy moors, and its advantages to the soil. No doubt, a great portion of the higher and more rocky part of Scotland is susceptible of little other improvement than planting; and, under timber, would produce more than ten times the income that it does in pasture; and the patriotic motive of embellishing his country, and enriching his countrymen, may excuse his having drawn the advantages of planting in rather high colours. Mr Cruickshank’s statement (as he says, designedly kept rather below the truth), that an acre of moor, of average quality, covered with Scotch fir, sixty years {310} planted, would contain 600 trees, value 10s. each, differs considerably from what has come within our experience. The timber of an acre of Scotch fir, sixty years planted in such waste ground as occurs in the valley of the Tay, will not average much more than one hundred pounds per acre on the spot, and laid down on the quay at Newcastle (the place to which the greater part of the Scotch fir on the east of Scotland is carried), would not produce L. 300 per acre.

In order the more to encourage planting, Mr Cruickshank runs into a speculative statement of the fertilizing influence of planting upon the soil, in rather a novel manner, leaving out the particular facts, which, he says, had come under his own observation, and adducing one as proof, furnished to him by another person unnamed. We have often had occasion to see ground, which had produced a crop of firs, brought under tillage without any marked fertility beyond the adjacent fields which had been under proper rotation of cropping, certainly inferior to what had lain for the same length of time in natural grass pasture. There is a particular instance in a slight rising ground (diluvial soil) in the Carse of Gowrie, where the fields, since the rooting out of the fir-wood, have not paid seed and labour in corn, though {311} under regular manuring and rotation. There are even varieties of pine, such as the loblolly, which are known to have an influence upon the soil where they grow poisonous to succeeding crops. Mr Cruickshank himself adverts several times to ground which had produced a crop of timber, being boss (hollow) from the roots remaining in the soil, and owing to this hollowness being unsuited for replanting till the roots were removed or consumed. We do not very well comprehend this hollowness, and ascribe the unsuitableness for replanting immediately, rather to exhaustion, or to the formation of something inimical to vegetation, than to any hollowness or manner of arrangement of the soil.

As the causes which promote or retard the formation, or which tend to dissipate the earth’s covering of vegetable mould—a covering, on the richness or thickness of which the fertility of ground, as well for most kinds of naval timber as for other products, is so much dependent, though of the greatest importance—have never, that we are aware of, been generally brought into view, we shall devote some space to their consideration.

In the first place, to give a fair specimen of our author, we shall transcribe several pages where he {312} has treated this subject with some ingenuity, and on which he appears to have bestowed considerable care.

“Those who have never had an opportunity of seeing old woodlands brought into cultivation, will scarce credit what has now been advanced, that the soil should be enriched by the production of wood, when the experience of ages has proved that it is always exhausted by other crops.”—“Trees draw their nourishment from a much greater depth than any of the grasses, roots, or different kinds of grain raised by the agriculturist. Most of the latter derive the whole of their subsistence from the part of the soil that lies within a few inches of the surface; but the former, from the superior strength and magnitude of their roots, are enabled to penetrate much farther, and extract food from the very rock which forms the substratum of a great portion, both of our cultivated and uncultivated grounds. This, though it does not account for lands being positively enriched by wood, makes it, at the same time, far less surprizing that trees should grow to a large size, and yet not exhaust the upper part of the soil in so great a degree as most of the crops cultivated by the farmer.

“There is another circumstance which gives ground in wood a great advantage over that in {313} tillage, which is, that the leaves of the trees are suffered to decay and rot where they fall, and, by this means, an annual addition is made to the depth of the vegetable mould. Now, the leaves of a tree may be considered as bearing the same proportion to the trunk and branches, in respect to the nourishment which they require, as the straw of corn bears to the grain. But the manure which cultivated land receives, is, in general, little more than the straw which grows on it after it has served for food or litter to cattle. Ground in wood, then, actually receives, in the annual fall of the leaves, as much enrichment as the farmer bestows on his land under tillage.

“Ground employed in agriculture is exposed at almost every season of the year to the full action of the atmosphere; and in the drought and heat of summer, much of its strength is evaporated. In land covered with wood, the case is entirely different, as from the shade afforded by the leaves and branches, very little evaporation takes place. This, then, is another reason that serves in some measure, at least, to explain the seemingly paradoxical fact in question. For, that evaporation has a very powerful tendency to exhaust land, by drawing off and dissipating the more volatile part of the matter which {314} assists in the process of vegetation, there can be no doubt, when we consider that any kind of dung may be deprived of the greater part of its strength by being long exposed to a dry atmosphere. Nor is it merely by preserving its own original substance that land in wood has the advantage of cultivated ground. Whatever is extracted from the latter in the form of vapour, falls again, when condensed, in the shape of rain or dew; but, instead of descending wholly on the same spots from whence it rose, it is, of course, diffused over the whole space which the clouds, containing it, may happen to cover, and woods and moors have as good a chance of receiving it on its return to the earth, as the ground in tillage. The part of it which falls, either on the cultivated fields or the naked wastes, may be again evaporated before it has time to be productive of any benefit; but the portion of it which the woodlands imbibe is retained to enrich the soil; for, the umbrage excluding the rays of the sun, there is no possibility of its being extracted a second time. Land covered with trees, therefore, while it never loses any thing, receives, with every fall of rain, or of dew, a tribute from the riches of the cultivated part of the country. The advantage derived from this source is greater than will be credited by those who are not aware how much {315} of the substances proper for vegetable nutriment are exhaled from the land in a gaseous state during the dry season of the year.

“But the principal way in which wood becomes instrumental in enriching land still remains to be noticed. When trees attain a certain size, they attract multitudes of birds, which build their nests and seek shelter among the branches. The dung of these animals is the very richest kind of manure which can be applied to land, and possesses, at least, three times the strength of that commonly used in agriculture. The quantity of it produced during the long series of years which trees require to reach maturity is, especially where large colonies of crows take up their abode, very considerable, and must have a powerful influence in improving and fertilizing the soil.

“I ought not to omit here to mention, among the causes why ground is improved by producing wood—the minuteness into which its particles are divided by the roots and their fibres. On taking up a young tree, or even a gooseberry bush, and shaking the earth from its roots, we find the mould that falls from it as completely reduced to powder, as if it had been passed through a fine sieve. Now, the fact {316} seems undoubted, that land is much increased in fertility by being brought to this state.”

Whether a greater accumulation of vegetable mould or enriching of the soil, would take place under a system of rotation of crops, stirring of the ground, and manuring, or under Nature’s own system of management—whether, under forest, or under the rich leafy grasses depastured by cattle, is a question of the greatest intricacy, and only admits of local decision, being dependent upon climate, soil, and circumstance. From our author’s statements, it would appear that his mind had only ranged along the surface of the subject. He has not taken into account the quantity of root which herbaceous vegetables annually leave in the ground—in some kinds little inferior in bulk to the portion above ground. We have traced oat and wheat roots running down into clay five and six feet (as deep as those of many kinds of trees), extremely numerous, and fine as human hair. He seems not aware that the bulk of yearly vegetable produce is much increased by culture, alternate cropping, and extraneous manure, such as lime, mixture of earths, sea-ware, bones. He has not considered that the annual dead roots within the soil, and the vegetable and animal manure, and the {317} sward and the stubble ploughed down, conduce much more to enrich and thicken the soil than the tree leaves, blown about by the winds, and nearly dissipated into air, before the residuum fixes as a part of the soil; and also that ploughing is often beneficial to shallow soils, by mixing the thin covering of mould with the pure earth of the subsoil,—the vegetable soil-matter, from consequent deeper cover, and more equable moisture, not losing so much by evaporation, and at the same time being more efficacious as nutriment to the vegetation. He seems unacquainted with the fact, that the matter of wood and tree-leaves, especially of the resinous kinds, and those containing much tannin, if not actually pernicious, have very little fertilizing effect—saw-dust has generally no manuring influence, but turns into peat. He also appears to be ignorant, that some kinds of vegetables draw more from the air and water, and others more from the earth; and, especially, that vegetables in a moist climate, depastured or cut before maturity, exhaust the soil much less than when allowed to seed. In Britain, soils, particularly those of good quality, become richer, and thicken more under pasturage, than under any other common vegetation. This is owing to the manuring of the cattle—to the natural grasses not being what is termed scourging plants, especially {318} when not allowed to seed—to the complete cover of the ground by the leaves—to the quantity of root which dies annually—and to the mould thrown up by the red earth-worm, renovating the surface, and partly covering the moss and decayed leaves and old bulbs. It is a curious fact, that, under pasturage, fertility should increase in Britain and diminish in Australia. An uncropt deep cover of grass appears necessary to shelter the vegetable soil-matter during the arid heat, and even to protect the roots from being burned out, in the latter country. And the manure of cattle, instead of being covered by the luxuriant herbage before it is desiccated, and enriching the soil as in England, is, in New South Wales, under the powerful sun and arid air, quickly reduced to dust and dissipated.

The fertility of soils may also be quickly increased, and the vegetable cover thickened almost to any extent under tillage, by first rearing a quantity of large growing annual vegetables, and when nearly full extended, burying this green vegetable produce in drills, resowing the ground immediately with another fast growing kind, and proceeding thus continuedly.

The influence of birds in enriching forest soil, is exceedingly limited, and is chiefly perceptible, not in continued forest, but in some detached portions or {319} clumps of park trees, which colonies of rooks or other large birds frequent.

Of the natural grass which Mr Cruickshank states succeeds in woods to the original heaths, and which he describes as affording such excellent tender food for cattle, we can only say, that either the woods must have been unprofitably thin, and the trees naked, or that he has completely mistaken the quality of the herbage. The grass of woods is unhealthy food for cattle, and generally not relished, being rendered unpalatable and noxious by the resinous and bitter droppings from the tree leaves, and by the bitter and nauseous juices generated in the soil by the roots of trees, which the herbage roots draw up. In dry soils, there is sometimes an accumulation of whitish substance within the ground, around the roots of trees, which some refer to excrementitious deposit61, but which, we think, is rather the produce of a subterraneous vegetable, of the nature of a fungus or mould. Wherever this has increased to a considerable extent, we believe old forest ground will be found of great fertility. {320}

The friability and minute division of the soil to which Mr Cruickshanks refers, existing around the bulbs of trees, can only be of utility where the soil is too adhesive. Light soil is often injured by being cropped by plants which tend greatly to reduce adhesion—what the farmer styles being driven: besides, all luxuriant annual crops render adhesive soils friable; and, remaining for a time under natural grass, gives what is termed a turfiness to soils, which continues for several years, and which renders both adhesive and light soils more productive, preventing the adhesive from sinking down into mortar under cultivation, and the light from losing all adhesion or granular arrangement.

There is, no doubt, a disposition to accumulate vegetable deposit in forests, from the moistness, coolness of the ground, and shade, not tending so much as the sunshine and exposure of open country to dissipate or volatilize the residuum of the decayed leaves and roots. In a lower latitude, beyond the line of peat formation, this will have some influence to increase the depth and richness of the vegetable mould; but, in Scotland, where cold till bottom prevails, more injury will result from forest tending to throw the debri of vegetation into combinations unfavourable to the nourishment of plants (such as peat {321} and compounds in which iron forms a part), than advantage, from the dead vegetable matter not being so much dissipated by aration and exposure to the sun. We have often observed the effect of remaining for a length of time in a state of considerable dryness, dissipating the vegetable part of the soil, in some of the old infield clays, where the crown of the large ridges are raised up a foot or two above the original surface-level. At the crown of the ridge, the vegetable clay mould often only extends down about nine inches from the surface, the subsoil immediately under being nearly void of vegetable matter, and extremely close tenacious clay,—a solid foot of it, though of equal moistness, being nearly double the weight of the same bulk of the vegetable clay mould above it. From this clay, almost purely mineral, being a little above the original surface-level, there can be no doubt, that at one time it consisted of the vegetable surface mould of the country, heaped up by repeated ploughings, and that it has gradually lost the vegetable part. The depth of vegetable soil, near the furrows of the ridges, is generally found to be greater than at the ridge crown.

The same dissipation of vegetable matter takes place when a ditch has been dug in clay ground, and {322} the excavated earth thrown up to form a dike on one side. On removal of the dike, the original surface, which no doubt, at the time the dike was formed, consisted of vegetable clay mould similar to the surface around, is always found to be close, heavy, poor clay, containing little or no carbonaceous or vegetable matter. In this case, from the draining effect of the ditch, the original surface under the dike must have been drier than the subsoil of the crowns of the ridges.

The difference of depth and richness of vegetable mould, may nearly always be referred to existing causes, such as the original surface (diluvium, or decayed rock), being a combination of earths favourable to vegetation; occupying a genial situation; being favourably placed with regard to moisture, that is, less or more moist, according as the original surface has been clayey or sandy, or open or close bottomed; and is in no way connected with those flood torrents to which we owe the diluvium deposits themselves—tills, sand and gravel, in which we have never found any vegetable matter, excepting in the coaly or mineralized state.

Unless in the case of alluvium, or of drift sand, or where surface earth has been rolled down from {323} heights, or been forced by man62, soil is seldom found to exceed 6 feet in depth, and that only in warm moist situations, propitious to vegetation. In Scotland we never have seen it exceed 3 or 4 feet in depth where its accumulation had not been aided by the above causes. The most common depth is from 6 inches to 2 feet; but, in many of our sterile districts, the surface hardly deserves the name of mould, containing very little vegetable matter, or that matter being unavailable from the presence of tannin.

It is a well known fact, that summer-fallowing always dissipates a portion of the vegetable matter in the soil, although it may, at the same time, tend to fertility, especially in adhesive soils, and where the climate is not very arid and warm, overbalancing the loss from dissipation by the advantage resulting from aëration and absorption of gases and heat, and the sun’s rays; by the mechanical disposition and comminution from being thoroughly dried and then moistened; and, probably, by the formation of salts, {324} stimulative to vegetation; or, as it has been thought, by the resting for a season. In the case of any tannin or inert vegetable matter existing in the soil, the heat and drying will tend to reduce these to a condition suitable for vegetable food. In the West Indies, when a summer fallowing is resorted to in order to get clear of the weeds, the fertility of the ground is considerably lessened, from the evaporation or burning out of the putrescent or carbonaceous matter. Were the fallowing continued for several successive seasons, there is no doubt that the whole matter, which, combined with earth, forms mould, would be dissipated.

About a century ago, it was the practice, in our neighbourhood (an alluvial clay district), to build up the soil of the fallow division, furrow deep, into thin dikes, or walls, about 5 feet high. This was done in early summer. After being dried and aërated by the summer’s drought, the dikes were levelled down in the autumn and sown with wheat. This system was considered so fertilizing as to counterbalance the labour and the loss of a crop.

Our own practice has proven that there is scarcely any manure more effective for one crop, particularly of spring sowing, than the clay of old mud walls of {325} houses, though applied in no larger quantity than is usually given of farm-yard manure, and though the clay appear quite free from vegetable matter. It is improbable that the resting of the clay from production could have any effect to occasion this fertility. We considered it to arise chiefly from a quantity of nitre having been formed in, or deposited about, the walls from their long proximity to animal effluvia and to atmospheric air. The fertilizing effect of the dike system of summer-fallow, and even of the present system, may also depend in part on the formation of nitre, well known to be a powerful manure or stimulant in this country. In dry seasons we have scraped together handfuls of salts, partly nitre, from the exposed surface of clay-banks. Should a considerable part of the fertilizing effect of fallowing arise from the formation of nitre, the application of lime and putrescent manures to fallows, in the early part of summer, will be advantageous, as the presence of both are favourable to the formation of nitre. Of course, the utility of encouraging the formation63 of {326} nitre or other salts, combinations of potassa or of soda, will depend on the climate, whether much or little rain falls, and whether the rain water goes off by evaporation or by drainage. In the case of little rain, or the rain-water being nearly all evaporated, nitre and other salts will accumulate in the soil, so as, from their excess, to be injurious to vegetation; whereas, should much rain fall, or the rain-water be chiefly carried off by drainage, vegetation may languish from deficiency of these salts, there being less deposition of the salts, or the salts as they form being washed away. The same will apply to the graminivorous animals. Sea-salt, perhaps also nitre and other salts, will be serviceable in a moist country, or far from the sea, where the plants and water contain little saline matter, and probably pernicious in a dry climate, where the plants and water generally contain much saline matter.

In the portion of the earth from the Atlantic eastward, through Numidia, Libya, Egypt, Nubia, Arabia, Persia, as far as the Indus, from the enormous ruins, and other vestiges of dense population, as well as from ancient records, there must have {327} existed a considerable depth of vegetable mould covering, where now little is left but pure sand, baked clay, bare rock, and saline encrustations. From the footing which an industrious and brave nation has recently so honourably acquired in this territory, may we not hope that the tide of arid sterility, dissipating the vegetable covering, will be turned, and that through European enterprise and mechanical science, by means of steam and wind power, a system of irrigation will be introduced which will reanimate this dead portion of the earth—spreading forth again perpetual spring, strewing the desert all over with herbs, and fruits, and flowers, converting the sirocco into a breeze loaded with fragrance, and reproducing, in profusion, all the delights of the gardens of Hesperus? From the carbonaceous or soil-matter being burned out, and from the quantity of saline deposit, a very considerable time will, however, elapse before production be generally extended, and the desert so far circumscribed, and the ground cooled so much, as to condense a sufficiency of rain and dew, that a new vegetable mould cover may be formed.

But to return from our wide exclusion, we observe, that Mr Cruickshank states, page 25, “that any land that is proper for Scots fir will be found to answer well with the larch.” This observation, with {328} what he says of larch “being heavier in proportion to its bulk” than Scots fir, and that “spruce is very easily wrought, and tries the carpenter’s tools less than any other kind of wood used in building,” would lead us to suspect that our author has had a very limited acquaintance with his subject. A number of different soils will produce large Scots fir where larches will be generally rotted and hollow in the heart, by twenty years of age64. This ignorance of our author is the more glaring, as it is coupled with {329} some severe strictures on planters in general for their ignorance of the proper location of trees. He says, “Scots fir, on soils of a fertile character, is short lived, and the excellence of its timber is in proportion to the slowness of its growth.” This is erroneous. We would rather say it is short-lived in bad soil: Memel fir (Pinus sylvestris), is of very superior quality, very large growthed, and of great age. He also asserts “elm prefers a strong clay soil, and it is perhaps impossible to bring this tree to the utmost size it is capable of attaining in land of a different quality.” This is also erroneous. We have seen very beautiful large Scots elms grubbed out from a soil of pure gravel, and we can show thousands of instances where Scots elms do not thrive well in clay—in rich as well as poor clay. We are aware that in every volume treating of numerous facts, such as Mr Cruickshank’s, many inaccuracies may always be picked out, but the above are rather too prominent.

Mr Cruickshank censures the practice of covering fir seeds one-half inch deep in England, referring the {330} demand there for Scots plants to the seeds being thus buried in place of being sown, and states that they should only be covered one-fourth of an inch, as is the practice in Aberdeenshire. He also reprehends the author of the Encyclopædia of Gardening, on account of some directions which this author has given, to form, by forcing, a fine friable soil, suitable for the delicate seeds of trees, where this does not previously exist. Now, we should consider that the difference of climate between the neighbourhood of London and Aberdeen would require a difference of cover nearly equal to this; and that forcing a friable earth for seed-beds was absolutely necessary, in the very adhesive clays around London, and so general in the more recent formations of the south and middle of England, although superfluous in the north of Scotland, where sandy or light soil is sufficiently abundant. Seeds, under a moist cloudy atmosphere, will vegetate without cover at all; but in situations where the air is arid in spring, with much sunshine, a covering of some depth is necessary, and that covering, where the rudiments of the plant spring out weak and delicate, is required to be soft and friable, a good absorber and retainer of moisture, and not disposed to run together with rain, or crack with drought.

Mr Cruickshank gives an account of our different {331} forest trees, neither very accurate nor interesting, but, luckily, not very tedious. He then proceeds to treat of nursery, sowing, transplanting, and choosing of plants, where many sensible, though some of them common-place, observations occur, of much use to the generality of planters. His views, however, of the proper manner of planting seedlings in the nursery, are defective. The best method of planting these—neither by laying, nor by dibbling—is first to stretch the line and make a furrow, level in the bottom, as broad as the roots may stretch, with the inner side straight and steep. One person then holds the plant erect in its berth, from two to four inches from the perpendicular side, according to the general size of the horizontal roots, so that the fibres may be regularly spread; and another person throws on the earth from the place of the next furrow; the placer of the plants footing the earth to the roots as he proceeds, or after the row is completed.

The following observations of Mr Cruickshank are worthy the attention of planters:

“Proprietors should not attempt to raise seedlings, but purchase them from professional nurserymen, and place them in a succession nursery of their own. A proprietor may, in general, purchase seedlings much cheaper than he can raise them; while the case {332} is just the reverse with regard to plants of a greater age. In raising seedlings, much skill and attention is requisite, which the professional man can always command at a much more reasonable rate than the proprietor. In the treatment of plants after they are removed from the seed-bed, the rent of the ground is the chief source of expense, as any common gardener will be able to manage them.”

“A general, and a very gross error, in purchasing plants, is to consider those as best which are the largest in proportion to their age. This absurd principle of selection makes those nurseries most frequented by customers which least deserve to be so, such, namely, as are situated in the richest soils, surrounded by the closest shelter, and stimulated by the greatest quantities of manure. It is necessary, no doubt, that plants should be of a size to suit them to the situations for which they are intended; but if they have attained this size sooner than the due time by being forced, they are in the worst state imaginable for growing in a barren moor, or on the bleak side of a mountain.”

“Plants are often much injured, though raised sufficiently hardy in other respects, by being too much crowded in the nursery line.”—“The surest method that I know of enabling those who have little {333} experience, to ascertain whether plants, in the seed-bed, are too much crowded or not, is to compare such as grow on the verge of the alley with those in the interior. If the girt of the latter be equal, or nearly so, to that of the former, the plants have sufficient room.”—“When plants have stood for several years in nursery lines, if they are too much crowded, many of their lower branches will be sickly or withered, or the stems will be entirely devoid of branches, excepting within a few inches of the top. This is a mark so plain that no one can mistake.

“Care should be taken not to purchase plants which betray symptoms of disease. When larches not more than three years old cast the whole, or even the greater part, of their leaves, just when the winter commences, it is a sure sign that they are in an unhealthy state, and that many of them will die in the course of next season; for, under this age, the larch should retain a considerable quantity of its old leaves till spring.”—“There is also a minute white insect, which is fatal to the larch in plantations, that sometimes attacks it in the nursery after it enters its second year; on this account, it is proper to examine the larch plants the summer previous to purchasing them.”—“Scots fir maybe regarded as sickly, when the points of the leaves become withered, or {334} when they change their naturally dark colours into a faint yellowish green. Any vestige of withering on the spruce or silver fir, is a sure prognostication of approaching decay. Any kind of fir which has lost its leader may be considered useless.

“When plants are packed up in mats for the conveniency of carriage, strict orders should be given that those which carry their leaves in winter be taken up when they are entirely free from moisture. If they be pulled wet, they will heat and get mouldy in the packages. In the course of a few days good plants are often spoiled in this manner.”

Mr Cruickshank does not swerve from the common foolish system, of inculcating a determinate character of soil as generally necessary for each kind of tree. We are angry with the dulness of the writers on location of timber; they will not comprehend that a tree has two ends, by both of which it draws moisture, though from different elements, earth and air. The dullest clown is sensible he requires to drink more under an arid sun than under a drizzling rain. The same holds of trees; if there be little evaporation of moisture from the leaves, and if the leaves, instead of exhaling, can frequently even imbibe water, from the plant occupying an elevated situation, where the air the greater part of the season {335} is cool, and nearly surcharged with moisture, the most porous, driest soil (sufficiently damp in such a situation), will generally be the most suitable; and trees of every kind will prosper in sands, in which, under a dry atmosphere, they would not have survived one summer; whereas in arid, warm, low country, the deepest, dampest loams and clays are generally the best suited for timber, provided water does not stagnate. And, besides, we have found varieties of the same kind or species of tree, some of them adapted to prosper in dry air and soil, and others in moist air and soil. Although the above causes prevent a positive limitation of certain kinds of trees to certain soils, yet there are some which have superior adaptation to moist soils and others to dry; some whose roots, from their fibrous soft character, can only spread luxuriantly on light, soft, or mossy soils, and others, whose roots have power to permeate the stiffest and most obdurate. The above explanations will account for much of the incongruity which we find in authors regarding the adaptation of certain kinds of timber to certain soils.

In describing the soils suitable for different kinds of trees, Mr Cruickshank mentions, that “the Scots fir will thrive in very barren situations, provided the soil be dry. Dryness is, in fact, the {336} most indispensable requisite in order to produce a good crop of Scots fir, and it is never advisable to plant this tree in very moist ground, or where draining is necessary to carry off the surface water.”—“Stiff land seems decidedly hostile to its growth.”—“On a deep rich soil it grows very fast, attains a large size, and soon decays. In these circumstances, its wood is spongy, and of inferior value.”—“The most important precept that can be delivered with regard to this tree, is never to plant it either in wet or very stiff land.”

“The larch is also a very hardy plant, and is sure to thrive on any land that will answer for the Scots fir. It is, however, less delicate in its choice of soil than the latter, and will grow in a much greater degree of moisture.”—“This tree is one of the surest growers we have in barren soils.”

“The spruce is as partial to moist land as the Scots fir is to dry; and in this particular these two species stand directly opposed to one another.”—“Spruce may indeed appear to thrive in a dry situation for a few years; but by the time it reaches ten or twelve feet in height, its lower branches will decay, and after that period it will make little progress, but remain even a cumberer of the soil.”—“ Spruce seems to be most partial to a cold stiff clay: it is, {337} however, a very hardy plant, and not very nice in its choice of soil, provided it have enough of sap.”—“I do not mean such as is deluged in winter with stagnant water. This is incompatible with the growth of wood of every kind.”—“The silver fir and balm of Gilead will answer in the same kinds of land as the spruce.”—“They, together with the spruce, are invaluable for where the soil is deep peat-moss, as neither the Scots fir nor the larch will thrive in it.”

There is in the above quotations, in common with many of our opinions (formed hastily upon a too partial acquaintance with facts), a considerable proportion both of truth and error. Such sweeping assertions will, however, generally command the assent and admiration of the reader. From the enjoyment the mind has in forming clear conceptions and reaching conclusions, from its love of order, and from its disposition to cling to every thing like definite, unfluctuating arrangement, to assist its limited powers of comprehension, we are led away by the author, who reduces the character of natural phenomena to great simplicity, although in reality exceedingly complicated.

Scots fir, it is true, has rather a superior adaptation to dry, sharp, and rocky soils; yet there are many {338} situations of poor wet till and clay, and even peat-moss ground, where it will be advantageous to plant Scots fir in preference to any other kind of timber; for this plain reason, that no other kind will thrive so well in those cold moist moors. Both Larix and Abies have a much narrower range of adaptation than Pinus sylvestris. Larch will not thrive in the dead sand nor till flats of the low country, often not in the dead sand and till of rising grounds, in both of which the Scots fir, if allowed sufficient room for side branching, will reach good-sized timber. There is a considerable formation of peat-moss near Dunmore, in which the Scots fir has shown superior adaptation to the Norway spruce. We have also seen, in the moss of Balgowan, Perthshire, fine thriving Scots firs, many of them two feet in diameter, growing in very moist, rich, mossy loam,—so moist, that although in a rather protected situation, a number of the trees, while young, had been laid on their sides by the wind, and were growing luxuriantly in the form of a quadrant of a circle, with as much as six and eight feet of the stem upon the level ground, affording a curve sufficient to reach from the keel of a vessel to the deck at midships. We examined the timber of several of these, and found it superior to the average of home P. sylvestris. The superior {339} quality of the timber may be ascribed to the richness and moisture of the soil, and to the full branching of the trees from their rather open arrangement. There is nothing which conduces so much to the good quality of Scots fir as exposure. Under the great shelter of the close planted woods, the timber is soft and porous, without much resin; but under great exposure, especially to dry air, the timber is hard, close, and resinous. This is, however, considerably modified by the soil.

The quality of natural grown timber is considered superior to the planted. Is this occasioned by the former having generally more branches and leaves in proportion to the length of the stem, and being more exposed than the latter? Can root fracture at transplanting, or the kiln-drying of the cones, have any influence to diminish the strength of the fibre or quantity of resinous deposit? We have been told by several old people, in the neighbourhood of Dunsinane, that Scots fir plants, brought more than half a century ago from Mar Forest to Dunsinane Wood, succeeded much better than some which had been procured from nurseries, and also produced better timber.

Clay is assuredly not the proper soil for spruce and silver fir; their exceedingly numerous, soft, fibrous, moss-like rootlets, require an easy damp soil. {340} We have tried a number of kinds of abies, in both dry and moist clay, and have found they did not grow so luxuriantly (thrive so well) as Scots fir or larch. The silver fir shewed superior adaptation to any of the other kinds of abies.

Almost in every instance where we have seen the silver fir and Norway spruce (by far the best spruce for Scotland) growing together, the former was the superior. The timber, in the lower part of the stem, is harder than that of the spruce, but freer and more porous in the upper part. It is probable that the silver fir will not thrive in so elevated or so moist a situation as the spruce, but in all favourable soils it merits a preference.

We now come to a very important part of our author’s volume—an account of the most economical, and, as he says, the most successful, mode of planting moors and bleak exposed mountains, but which is brought forward by him under no limitation to place. To the invention of this method, our author lays no claim; he merely describes the practice in a clear and judicious manner.

“The most proper time for removing firs from the nursery to waste land, is when they are two years old.”—“The experience I have had enables me to say, with as much confidence as I can speak on {341} any point whatever, that the longer any fir is allowed to remain in the nursery after it has attained two years’ growth, so much the less chance is there of its success when removed to its final destination.”—“At this period (two years’ growth) larches may be obtained transplanted, as it is customary to put considerable numbers of them out into nursery-lines when they are one year old. Such plants have better roots than those that have remained in the seed-bed till they are of the same age; but as their price is considerably higher than that of the latter, it is somewhat doubtful whether they are so much superior in quality as to compensate for the greater expense. At all events, healthy larches from the seed-bed have never failed to give satisfaction when properly planted in soil suitable for them. Other species of fir are scarce ever transplanted in the nursery till they are two years old, so of this age there is no choice left but to take them from the seed-bed.”—“Birch, alder, and mountain ash, succeed well when removed from the nursery in their second year.”—“Beech and plane do not succeed well unless they have stood some time (two years at least) in nursery lines, after having been removed from the seed-bed.”

“The pitting system of planting should be {342} adopted in every instance in which the plants exceed two years old.

“The expense of planting was much reduced by the introduction, about a century ago, of the notching system. Of this there are two varieties, the oldest of which may be described as follows:—One person makes a notch in the ground, or rather two notches crossing each other, with a common spade, raising the sod by bending down the handle of the instrument, till the notch become wide enough to receive the roots of the plant. An assistant, with a bundle of trees, slips the root of one into the aperture thus made for its reception. The spade is then withdrawn, and the closing of the sod on the root is assisted by a smart blow of the heel of the planter. In this way two persons, well practised in the work, will put into the ground between five hundred and a thousand per day.

“This system was much simplified about fifty years ago, and rendered so expeditious, that it seems in vain to look for its receiving any further improvement. Instead of the spade, an instrument of nearly the same shape, but so small that it can be wrought with one hand as easily as a common garden-dibble, was introduced, and is now known by the name of the Planting-iron. With this, a notch is made in {343} the ground to receive the root; and owing to the portability of the tool, and its occupying but one of the hands, the person that works it requires no assistant, but, carrying a parcel of plants in a wallet before him, he singles out one with his left hand, inserts it in the notch, withdraws the implement, fixes the plant with his heel, and proceeds with as much apparent ease as if he were performing the operation in the soft ground of the nursery. In this way of planting, the workman goes forward in such a line as he can judge of by his eye; and as it is extremely difficult to see the plants after they are put in, especially if the heath is pretty long, he sets up poles in the first line, to enable him to keep the second a due distance from it; and in planting the last mentioned, he removes these poles into it as he comes opposite to them, which then serve as his guide in planting the third; and thus he proceeds till he cover the whole ground. The lines thus formed are necessarily so zig-zag, that when the trees grow up, they do not seem to have been planted in rows.

“In this way, an expert workman will plant between three and four thousand young plants a-day, and do it so perfectly, that the fault will not be his if a single individual of the whole number fail to {344} grow. I have assisted in planting, according to this plan, upwards of three thousand acres in Aberdeenshire; and, in all that extent, I know not of a single instance of failure, where the plants were in a healthy state when put into the ground, of the proper age and varieties, and suitable for the soil.”

“To plant well and expeditiously in this way, requires considerable dexterity on the part of the workman; and where raw hands are employed, it will be necessary to have some person to teach and superintend them.”

Mr Cruickshank disposes of the old cross system of slit planting by the spade, with very little ceremony; as it would almost seem, without being able to appreciate its merits. It is, in fact, a totally different mode of planting from that by the flat dibble-planter or planting-iron, and is well adapted for all plants with horizontal roots, and which have stood from one to three years in the nursery line. By first striking the spade in perpendicularly, as deep as the turf-soil, by again striking it in at right angles to the end of the first cut, in the form of a T, and bending back the spade, the turf-soil is raised from a horizontal bed, and the first cut opened so wide as to admit the root, which {345} inserted and drawn a little along by an experienced hand, and well tramped down, has its rootlets disposed over the horizontal bottom almost as regularly and well adjusted for growing, as can be done by pit-planting. This practice is sometimes performed singly, a clever workman managing the spade with one hand and the plants with the other, and inserting 1000 each day. The plants suited for this system are fully double the size of those suited for the flat-dibble system, and are purchased at about one half more price, thus enhancing the cost of planting to £1, 10s. or £2 per acre; but in many situations, especially where the herbage grows freely, affording an earlier growth, and more regular success, sufficient to balance the greater expense ten times over.

Although the cross-system of slitting is the best for commanding general success, yet wherever the flat dibble planting can be depended on, it merits a preference, as from the smallness of the plants, the roots receive less fracture and derangement in the woody state, and the process comes nearer to raising from the seed in situ.

The expense of each system per acre, will be nearly as follows:— {346}

Although our author speaks so confidently of the success of transplanting out firs at one and two years of age, yet this must only be taken under limitation to the country in which his experience has lain,—the barren mountains and moors of Scotland, where the vegetation of the heaths is extremely slow, and the herbage both thin and short. Were these small plants used in the superior climates of England and Ireland, where the vegetation of the grasses, and {347} other natural occupiers of the soil, is very luxuriant, there would scarcely be one in a hundred that would ever be seen after the first spring, unless a very expensive cultivation to check the weeds were resorted to. To effect economical planting in these soils, it is necessary to have the plants sufficiently large, not too close together, and placed in rows, that a mower may be able to distinguish them among the herbage while he cuts it down; or what is much better, that the spade or plough65 culture may be {348} practised, and potatoes, turnips, or other green crop, raised among them, without the plants being overwhelmed. In case of grass production, the oftener during the season the young plantation is mown, the more advantageous, as well that the plants may be the more easily distinguished, as that the lower branches may not be smothered, nor the soil so much exhausted and dried by the blooming and seeding of the herbage; of course, a short scythe is required, and also a very careful mower.

Speaking of the best season for planting, Mr Cruickshank states:—

“In wet and swampy soils, as well as in land, whether dry or moist, whose surface is bare, I would be inclined to prefer the spring. Wet land swells to such a degree, that plants which have not had time to take a firm hold with their roots, are almost {349} inevitably thrown out.”—“These remarks have reference only to the system of planting by notching: when the pitting system is adopted, it fixes the plant so thoroughly, as to render the utmost power of frost incapable of doing them any injury.”—“The utmost limits of the planting season may be estimated from the middle of October to the middle of March.”—“I am a decided advocate for thick planting, and would advise that no fewer than 3000 trees per acre be planted in good land, nor a less number than 4000 when the soil is of a middling or inferior quality.”

Mr Cruickshank must surely have had little acquaintance with soft, spongy, close-bottomed soils, or he would not have asserted that pit-planted trees are not subject to be thrown. If planted in the early part of winter or autumn, trees of the usual size, which have remained from one to three years in the nursery line, are very frequently thrown from such soils. This is caused by the freezing earth first catching fast hold of the plant at the surface, and afterwards swelling underneath from the enlargement of the freezing water in its pores, and from the open crystallized honeycomb arrangement which takes place by congelation. As the stem is fast to {350} the ground at the surface, and the earth subsequently enlarged underneath as far as the congelation proceeds, the roots below the congelation must of necessity be drawn upwards to the distance which the ground has swelled after the stem was fixed to the surface. The earth, on thaw, first loses hold of the plant at the surface, and then falls away as it contracts. Each successive frost and thaw during winter thus raises the plant a certain space, till by spring it often is so far extracted, as to fall over on its side. When the plant has stood a season, there is generally a tuft of herbage around its stem, which prevents the freezing in a considerable degree; and the roots having fixed in the lower earth, resist the pulling up so much, that the hold which the frozen earth has of the stem at the surface gives way, sometimes pulling off a portion of the bark, and the earth rises around the stem in place of pulling the tree.

Instead of the season for spring planting being over by the middle of March, we think that, in many of our wet moors, it should then only be commencing, especially under the pitting system. However, planting should never be deferred a day later in spring than what is absolutely necessary to render the ground sufficiently dry for the process. {351}

Mr Cruickshank’s opinions regarding pruning and thinning are generally not very incorrect. His commencing sentence on pruning, that “most deciduous trees, if left to themselves, have a tendency to grow with short trunks, containing little timber, and to waste their strength on large unwieldy tops,” would, however, lead us to form a different conclusion. The very tall, clean, straight, deciduous trees, in the American forests, give a sufficient answer to this. We like his remark respecting thinning, that “it is only efficacious when applied as a preventive, not as a cure.”

Mr Cruickshank next brings forward his plan of raising oak forest, which appears to have been his own invention, although invented before. Whenever mice and other gnawers (glires) are not very abundant, it, if properly executed, would seem to be the best method of raising oak forest; and, indeed, in many situations, the only practicable one. Mr Cruickshank’s method coincides nearly with Mr Sang’s, only he does not carry his system of protection so far as Mr Sang, in first raising belts of the most hardy kinds of timber, distributed to windward of, and intersecting the place intended to be planted, in such a manner as to afford the best possible shelter from the coldest most destructive {352} winds. Mr Cruickshank, who has never carried his plan into execution, except in an experiment embracing a few yards, directs that the ground intended for oak forest should first be planted with Scots fir and larch, about 4000 to the acre, by the single-notch process, previously described, which can be accomplished under L. 1 per acre. As soon as these have risen to four feet in height, he prepares patches about two feet square and ten feet distant in the interstices, by digging the soil over, and mixing a spadeful of slaked lime carefully with the mould, taking out a tree whenever the interstices do not suit for the patches. He then plants, in the end of March or beginning of April, five acorns in each patch, about an inch deep, one in the centre, and the other four in the angles of a foot square, and gives them no farther attention for two years, except removing any overhanging low fir branch. He then goes over the patches, cutting out all the supernumerary plants, a few inches below the surface, leaving the most promising one on each patch, being very careful not to disturb any of its roots in cutting out the others. As these oak plants extend in size, he gradually removes the fir.

Excepting the bare plan itself, which is certainly very plausible, there is nothing in the description {353} of the practice—the preparation of the patches of ground to receive the seed and the subsequent management—which merits attention. His very particular interdiction of the use of manure is, to say the least of it, injudicious—as if it signified to the plant whether it were forced by the use of lime, or by a little putrescent manure, both of which Mr Withers would consider very advantageous; or as if there were much fear on our poor exposed wastes of erring on the side of rendering the plant delicate from over luxuriance; its constitution, on the contrary, would rather be strengthened. Mr Cruickshank, in directing the removal of the fir nurses, one thousand per acre to stand till they have reached twenty-five years, fit for roofing of cottages, and similar purposes; and five hundred till they have reached thirty-five years; his dividing a slaked boll of lime into five hundred spadefuls; and his bestowing no hoeing or weeding upon his seedlings, would show, without his admitting it, that he had never practised this mode of forming plantation.

Prefacing this system of rearing oak forest, Mr Cruickshank in rather a clever manner points out its advantages, and also the disadvantages and consequent failures of planting young oak trees in exposed situations. But after all his eulogy, we think he has {354} left something unsaid. The great disadvantage attending transplanting oaks to situations not very favourable to their growth, is, that the plant which, under any circumstances, receives irreparable and often mortal harm, from the severe injuries of removal, has to contend, in this mutilated condition, at the same time with the uninjured occupiers of the soil (the nurses or the native weeds), and with the unpropitious situation; whereas, when the plant springs up from the acorn a native, especially when it is assisted at first by weeding or hoeing, the part above ground being always in proportion to that below, and receiving due nourishment, it contends with the occupiers on more equal terms, and encounters the sterility of the soil, or the severity of the climate, with all its natural powers unimpaired.

As it is the natural condition of the seedling to grow up under the shelter of the parent tree, so also does it happen, that it rises under this shelter with greater luxuriance and vigour than when exposed to the evaporation, and parching sun, and battering wind, of the bare country.

We have admired the beautiful, straight, luxuriant, shoots of the young hollies, thrown out under shelter, and have compared them with the dry stunted shoots of the young holly in the open country, though in the former case their roots had to contend {355} with the roots of larger trees, and in the latter they had the soil to themselves. Experience has proved, that in exposed bleak situations, shelter is necessary to young plants. Transplanted oaks among the roots of young trees, so large as to afford sufficient shelter, very frequently do not succeed, at least without the utmost care in the transplanting, and a considerable deal of labour to prevent the roots of the shelter trees from starving the transplanted ones, unless a very propitious moist summer follow the transplanting. Raising from the seed, which obviates all this, seems therefore the only conveniently practicable way. Yet it must be owned, that the system of raising forests in situ from the seed, appears, as yet, much more successful on paper than on our hills and moors.

In endeavouring to confute the opinion, that the oak will not grow throughout Scotland, but in the milder and more propitious situations, Mr Cruickshank adduces the well-known fact, that large oak timber is found in almost every peat-moss.

This is a fact worth tracing to its cause. Under Nature’s own conduct, trees advance considerably further into elevated or cold inhospitable regions, than they would otherwise do, by means of the mutual shelter, and of the more hardy kinds acting as an advance guard. Yet there is a limit to this, as the {356} power of ripening seed is not increased by shelter in proportion to the power of growing—perhaps not at all; we instance the Spanish chestnut, which has scarcely ever been known to ripen seed in Scotland. Seed-grown trees will, therefore, under Nature’s arrangement, not be found extending much beyond the line of seed ripening. From nuts, acorns, and other seeds, fully developed, being found in elevated mosses in this country, other causes than shelter appear to have existed.

Before this country was so much overrun by men and oxen, a great deal of timber had existed, covering much of the superior land which is now under tillage. This consisted chiefly of the oak, Scots fir, birch, hazel, and alder,—the oak extending northward and to elevations, and ripening seed, and attaining to a size which it does not now do, either wild or cultivated, in the same latitude, neither here nor in any other portion of the world; which, along with some other facts, lead to the supposition, that the climate has changed a little,—in part, possibly, as we have before stated, from the gradual formation of peat, to which, overthrown oak forest, from the abundance of the tannin principle, has a great disposing influence, even under a warmer climate than present Scotland. The highest latitude to which a tree, or any other kind of plant, reproducing by seed, {357} naturally extends, depending on the ripening of the seed, and also on the power of occupancy, is however different from that where it will grow, when ripe seeds are procured from the coldest place where they ripen, and all the competitors removed; and under the system of shelter belts, hardy pine nurses, and seeds from the nearest place where they ripen, we have no doubt that oaks may be extended to a colder situation than Nature herself would have placed them in. For the higher more bleak portion of the country, we would recommend acorns grown in Scotland, in preference to those imported from England. We have several times observed wheat, the seed of which had been imported from England, sustain blight and other injuries in a cold moist autumn, when a portion of the same field, sown of Scots seed, at the same time as the other, and under the very same circumstances, was entirely free from injury. English acorns are also frequently heated in the casks in which they are imported, which must impair their vigour66. {358}

The part of Mr Cruickshank’s volume which we have analyzed, does not extend much beyond the first half: this portion is well worth a perusal. We have merely glanced over the remainder: it is a make-up scarce worth noticing. The language, on the whole, is easy and plain; and although the volume contains a considerable number of errors, in the pointing out of which we have not been sparing, yet will it form an excellent planter’s assistant to people who have ground to plant, and are ignorant of the process of planting.

We have now brought before the reader a pretty fair picture of the Forestry of the present day. Some may wonder that the written science of arboriculture should be so imperfect and inaccurate; but the knowledge of the art, and the power of communicating that knowledge, are of so different a {359} character, it not unfrequently happens, that those write who cannot act, and those who can, are incompetent to write—sometimes unwilling; besides, correct opinions on this subject, as on most others, are only just beginning to be formed. We have endeavoured to assist in disentangling the correct from the erroneous. It is impossible for the most wary always to avoid misconception of facts, but man merits the name of rational only, when he evinces a readiness to break from those misconceptions, to which the narrow-minded, the proud, the vain, and the creature of habit and instinct, cling so obstinately. As a friend, we have stood on no ceremony with our brother arboriculturists. We have laid ourselves open to their criticism, and we hope they will shew as little ceremony with us.