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This tribe of the order Coniferæ, at once the most useful, and the most plentifully and widely extended over the North temperate zone—that portion of the earth more congenial to man, and which contains about four-fifths of his numbers, has a similitude of character and qualities more distinguishable by one glance of the eye than by laboured description. It consists of a number of kinds, which again divide into families and individuals perceptibly different from each other. The following are those whose timber is best known to us: {64}

Scots fir, or Norway pine,	Pinus sylvestris.
Pinaster,	Pinus Pinaster.
Canadian red Pine14 (foreign),	* * * *
Pitch pine (foreign),	* * * *

And, though a little more distinct,

Yellow American, or Weymouth Pine,

Pinus Strobus.

Very little observation will distinguish these from the next useful great tribe of the Coniferæ with white wood, the Spruces and Silver Firs—Abies.

There are a number of foreign kinds of pine, some of great promise, recently introduced into Britain, but of whose adaptation for ship-building we cannot speak. Samples of the timber of P. laricio, P. tæda, P. cembra, P. maritima, P. rigida, &c. of British growth, may, however, soon be had of sufficient size for experiment. The common Scots fir is the only pine of British growth which has been employed as a naval timber; for which purpose, however, since the last peace, and the introduction of our larch, it is in very little demand.

An acute botanist, Mr. G. Don of Forfar, a number of years ago, gave a description of the varieties of cultivated Scots fir which had come under his notice. The following is an abstract of his observations: {65}

“Varieties of Pinus sylvestris.

“Var. 1st. The common variety, well known by its branches forming a pyramidal head, the leaves marginated, of dark-green colour, but little glaucous underneath, the cones being considerably elongated and tapering to the point, and the bark of the trunk very rugged. This variety seems short-lived, becoming soon stunted in appearance.

“Var. 2d, Distinguishable from the former by disposition of branches, which are remarkable for horizontal disposition and tendency to bend downwards close to the trunk. The leaves are broader than var. 1st, and serrulated, not marginated; leaves are distinguishable at a distance by their much lighter and beautiful glaucous colour, the bark not so rugged as var. 1st, and the cones thicker and not so much pointed, and also smoother. This tree seems a hardy plant, growing freely in many soils: this variety may be named Pinus horizontalis. Var. 1st, much more general than var. 2d, and also sooner comes to seed, which is also easier gathered from the position of the branches.

“Var. 3d, Is of a still lighter colour than var. 2d, being of a light glaucous hue, approaching to a silvery tint; its branches form, like var. 1st, a pyramidal head, but it differs remarkably in its cones from {66} both the former varieties; the cones of this seem beset with blunt prickles bent backwards, the leaves serrulated. This variety is rather more common than var. 2d; like it, it is a good tree.

“Var. 4th, The leaves somewhat curled or rather twisted, and much shorter than the others: this variety is very rare.”

Our observation does not go to confirm these subdivisions. We think they are little more distinct than the fair, the red15, the black haired, the fair, the sallow, the brown complexioned, the tall, the short, of the same community or even family of men. There is variation and individuality more or less strongly marked in all kinds of organized beings: at least those vegetables which have exposed fructification possess it; many whose fructification is secluded also possess it; and the others of more constant character, such as some of the Gramineæ, with a little art (removing their anthers before the pollen bursts forth, and applying the pollen of others as near to them in the chain of life as can be found to be different, or changing the circumstances by culture), can also be rendered equally {67} variable. These minor distinctions or individualities of vegetables become more perceptible as our observation closes in upon the object. We have never yet found one individual apple plant, raised from seed, to be the counterpart of another; but differing even in every part and habit, in bud, leaf, flower, fruit, seed, bark, wood, root; in luxuriance of growth; in hardihood; in being suited for different soils and climates, some thriving in the very moist, others only in the dry; in the disposition of the branches, erect, pendulous, horizontal; in earliness and comparative earliness of leaf, of flower, of fruit.

We hope the above remarks will not be lost on those who have the management of the sowing, planting, and thinning of woods, and that they will always have selection in view. Although numerous varieties are derived from the seed of one tree, yet if that tree be of a good breed, the chances are greatly in favour of this progeny being also good. Scots fir of good variety will thrive and reach considerable size and age, in almost any soil which is not very moist, or very arid and barren (such as our sand and gravel flats much impregnated with iron or other deleterious mineral), provided the plants from their earliest years have room to throw out and retain a sufficiency of side branches. This is especially necessary to their health where the soil is {68} ungenial, the resulting vigour often overcoming the disadvantages. From the pine being found chiefly in the light sandy districts on the continent of Europe, and in the sandy pine barrens of America, an idea has gone abroad that these barren districts are more congenial to it than the more clayey, the more rocky, or the richer vegetable mould; but its natural location in the barren sandy districts results from its being more powerful in this soil than any other plant of the country, not from preference of this soil. Should any one doubt of this, let him take a summer excursion to Mar Forest, where no other tree having been in competition with Pinus sylvestris, and where it is spread over the hill and the dale, he will observe that it prospers best in good timber soil, and though comparatively preferring an easy soil, and having superior adaptation to thin or rocky ground, that its taste does not differ very materially from that of the plane or the elm, the oak or the ash.

In Mar Forest he will also observe (if they be not now all cut down) several well marked individuals of the splatch pine, esteemed a very valuable and hardy kind; and with the right which a botanist has in a plant sown by nature, he may bear off some of the seeds, and endeavour to spread this rare indigenous kind throughout the island. Should he be unsuccessful in finding these at Mar, he may return {69} by Kenmore, where, on the side of the hill on the right bank of the Tay, near the confluence of the Lyon, he will find several trees, we think five, of this kind of pine, of considerable size, growing at one place, apparently planted: we were told the plants had been brought down from the natural forest farther up on the mountains. These are sufficiently distinct in character from the common Scots fir growing around, having a horizontal, straggling disposition of branches, the leaves being of a much lighter, different shade of green, and more tufted, and the bark of a yellower red, so as to merit a distinct name; and we should consider Pinus horizontalis as descriptive as any other, if it shall not appear to be only a sub-species of P. sylvestris. The descriptive name splatch fir, is from the prominences of the rugged bark not being in longitudinal ridges or flutes, but in detached flat oblong lumps, such as soft clay or mud takes when cast with force upon a wall. We, however, do not think this the same as Mr. DON’s var. 2d, at least we have noticed in our lowland woods raised by planting, such as Mr. DON examined, individuals here and there having less or more resemblance to his described varieties, but none of them approaching the distinctness of this alpine Scots fir. The proprietors of this kind of pine will confer a benefit on the public by causing the timber {70} be examined and compared with that of trees of equal size of the common Scots fir growing near, and making a public report of the number and size of annual growths, the number of these of matured and of sap wood, the comparative strength, density, quantity of resinous deposit, hardness, &c.

The Pinaster is a valuable kind of red-wood pine, with strong resinous timber, and from not having one-half the number of sap-wood layers of the common Scots fir, we should consider it deserving attention as a naval timber; but perhaps the small number of sap-layers is from want of climate: owing to the branches being larger, and, in proportion to their size, being joined to the stem with a larger swell than those of P. sylvestris, the timber is rougher with larger knots. In the very barren sand and gravel district near Christchurch, scarcely affording sustenance to lichens, and where even heaths will not grow, we have observed this tree make considerable progress, and outstrip the Scots fir in growth.

The Canadian Red Pine has been employed to a considerable extent in this country, both as planking and spars. It is inferior in strength and durability to the Baltic red pine, and would seldom make its appearance on this side the Atlantic while the Baltic was open to us, did not a very ill advised {71} duty obstruct the supply of the better article. This timber is sometimes supplied with a good character by the shipwright, as it is soft, pliant, and easily worked. The Canadian red pine has a greater number of layers of sap-wood than any other red pine we are acquainted with; we have repeatedly counted 100 sap-wood layers. We have never seen this kind of pine growing in Britain.

The most common American pine, with yellow timber, Pinus strobus, has been introduced for a long time back into Britain, it is said first by the Earl of Weymouth, thence sometimes named Weymouth Pine. This rather elegant tree requires a warm sheltered situation, as it is easily torn down by wind, from the weakness of the timber, which is inferior in hardness and strength to any other pine we are acquainted with; and from its slender needle leaf not having substance to withstand the evaporation of much exposure. Altogether, the kind appears rather out of climate in Britain, and, though the monarch of the pines in Canada, holds here but a very subordinate place. Although extremely tender and light, the matured timber does not soon decay when cut out thin and exposed to wind and weather, nor worm when kept dry in houses; but when employed in shipbuilding—remaining always between the moist {72} and dry, the condition most favourable to putrefaction, and surrounded by a close, warm, putrid atmosphere—it very soon, especially in masses, becomes corrupted. It requires more time to season or dry in the deal than any other wood, owing to the fineness of fibre, smallness of pores, and want of density. From this quality of parting with its moisture with extreme slowness, it forms convenient deck-planking for vessels on tropical stations, or when employed in carriage of unslacked lime, as the plank does not readily shrink and become leaky under the great evaporation occasioned by the heat and arid air. Yellow pine has generally about 40 growths of sap-wood.

We have had no acquaintance with American pitch pine as a growing tree. As a timber, it is superior in several respects to all the others, having a great deal more resinous matter, so much, as often to render it semitranslucent. It is strong and weighty, and is used as a naval timber for most of the purposes to which other pine timber is applied. It forms the very best bottom planking. The shipwrights of the docks at Devonport will attest its quality, as the bottom planking of the Gibraltar of 80 guns: this vessel carried home to England from the Mediterranean, a piece of coral rock of about ten tons weight sticking in her bottom, her preservation {73} in all probability resulting from the adhesive quality of this timber. Its great weight is, however, a considerable inconveniency attending its use as spars, and the abundance of resin, we should think, would unfit it for tree-nails; resinous tree-nails—probably from some derangement of the structure or disposition to chemical change produced in the resin by the very great pressure of the hard driving—soon corrupting and infecting the adjacent wood. In some cases we have also known very resinous Baltic plank decay soon in vessels. The pitch pine, from the quantity of resin, contracts little in drying, at least for a long time, till the resin itself begins to dry up. It forms the best house-floors we have seen, being strong and durable, continuing close at joinings, and the fibre not readily taking in moisture when washed.

Our red-wood pine, when come to some age, is in wet ground attacked by rot, which commences in the bulb and adjacent roots and stem, in a manner very similar to the rot in larch. The red-wood also approaches nearer to the outside where this rot exists, and on the side of the tree where the rot is greatest. Most of our planted red pine forest, especially in poor wet tills, and in all flat sandy moorish ground of close subsoil, fall by decay at from 30 to 60 years old. This decay is gradual, owing to the {74} difference in strength of constitution of the individuals. Closeness of rearing and consequent tall nakedness of stem, and disproportion of leaves to stem, would alone induce this in a few years longer even in good soil, excepting perhaps in protected narrow dells; but the decay commences much sooner when the soil is unfavourable, and is no doubt accelerated by the mode of extracting the seeds by kiln-drying the cones, and by using a weak variety of the plant. The approach of this decay may often be noticed, several years previous, in the saw-cross section of the stem mid-way up the tree—an irregular portion of the section appearing of a different shade, from breaking off free and irregular before the teeth of the saw, and not having so much fibrous cover as the healthy part. When Scots fir rises naturally, it is not nearly so subject to this decay even in very inferior soils: the plants having generally much more room from the first, do not rise so tall, have more branch in proportion to stem, thence are more vigorous. The cones not being injured by kiln-drying, may also account for this.

The fact that the red pine in Scotland has fewer sap-wood layers than the red pine of Memel or of North America, and also the fact that, in most situations in Scotland, the red pine soon {75} decays—soonest in the places where the trees have fewest sap-wood layers, and where the timber has been planted, that is, where the cones have been kiln-dried—is worthy of notice. Scots red pine has generally from 15 to 40 layers, Memel from 40 to 50, Canadian often 100. We consider the long moist open winter and cold ungenial spring in Scotland, and the till bottoms soaking with water, perhaps aided by the transplanting, and the kiln-drying of the cones, to be the cause of this early loss of vitality or change of sap-wood into matured. In Poland and Prussia, the earth does not remain so long cold and moist as in Scotland, but is either frozen or sufficiently warm and dry;—this occurs even to a greater degree in Canada16, and neither the Memel nor Canadian have any chance of being planted or kiln-dried.