Although larch timber be extremely durable in exposed situation, yet it yields to the depredations of insects fully as soon as any pine timber in close houses. We have proof of it in house-furniture about 50 years old, but it is considerably moth-eaten by apparently a smaller insect than common. Larch stools also disappear in forests sooner than the stools of Scots fir, being eaten by a species of beetle; and the sea-worm devours larch in preference to almost any other wood.
We have looked over some experiments conducted at Woolwich, in trial of the comparative strength of larch and other fir timber, where the larch is stated inferior to Riga and Dantzic fir, Pitch pine, {104} and even Yellow pine. Larch, in the districts of Scotland where it is grown and much in use, is universally allowed to be considerably stronger than other fir; and the sawyers of it have one-fourth more pay per stated measure. We, ourselves, have had considerable experience of the strength of larch applied to many purposes, and have found it in general much superior in strength to other fir. We have known a crooked topmast of this timber, to which the sailors bore a grudge, defy their utmost ingenuity to get carried away. We once had four double horse-carts, made (excepting the wheels) of peeled young larch of rather slow growth, for the carriage of large stones; these, by mistake, were made very slight, so light, that, without the wheels, a man could have carried one of them away. When we saw the first loading of stones nearly a ton weight each, two in each cart, and the timber yielding and creaking like a willow-basket, we did not expect they would have supported the weight and jostlings of a rugged road many yards; yet they withstood this coarse employment for a long time. The timber of larch near the top of the tree is, however, very inferior and deficient in toughness; and it is not improbable that the experiments above alluded to at Woolwich had been made with larch {105} timber deficient in strength from being a top. White larch has comparatively smaller and more numerous branches than any other of the Coniferæ; consequently the timber is freer of large knots, and has more equable strength, as well in small spars as when large and cut out into joists and beams, provided the timber be not too far up the tree. Larch, however, compared with pines and firs, has the timber much stronger when young, and several inches or below a foot in diameter, than when old and large: this may partly be owing to its deficiency in resinous deposit.
NOTES TO PART II.
- [10]. We have often preferred the terms kind, breed, family, individual, to genus, species, variety, subvariety, as the former seem less definite. Were nature true to the latter classification as employed by botanists, it would be convenient.
- [11]. In those we observed, we considered this last circumstance had a considerable share as a predisposing cause of the attack of the worm. Forests of Pinus sylvestris are sometimes destroyed by insects under the bark, in cases where it is difficult to decide whether external circumstances, such as a dry warm season, has been promotive of the increase of the insect itself, or has induced some disorder in the plant, rendering the juices more suitable aliment to the worm.
- [12]. Some nautical or technical terms have unavoidably crept into this work; we shall not presume to think any explanation necessary: Britannia would blush jusqu’au blanc des yeux, to the tips of the fingers and toes, did she think it were doubted that any of her sons, not doomed to unceasing mechanical labour, were unacquainted with these.
- [13]. It is termed by our professors Salix fragilis, or Crack Willow, from the small branches breaking easily at the junction of the annual growth—or, perhaps, Crack Willow, from the branches breaking with considerable report; or from the wood, while burning, frequently detonating or crackling, from the expansion of some aërial fluid within the fibres. Though named by their sapience fragilis, it is not weaker than other large growing willows, but stronger and denser; and, being harder in the small branches, they do not bend, but break when their bark and alburnum is driest, in winter. The timber is superior to that of Salix alba, or of any other large growing willow we are acquainted with, and is sufficiently pliant and tough.
- [14]. Red Canadian pine is generally termed Pinus resinosa; but as it is not so resinous as several other kinds, we consider Pinus rubra (rubra from the colour of stem and also of timber), which is sometimes used, more suitable. The pitch pine of the American United States should be Pinus resinosa.
- [15]. We think that in mankind the variations of the children of the same parents do not soften entirely—there would seem to be certain types or nuclei both of appearance and temperament around which external and internal character vibrates.
- [16]. The Canadian red pine resembles P. sylvestris or Norway pine so much, that it is usually styled Norway pine by the settlers: Though different, it is so nearly allied to P. sylvestris, that we consider the number of sap-growths may be referred to the climate and soil, and not to the kind,—that is, that, were it grown in Britain, if it did not at first, it would in the course of time come to have fewer sap-growths.
- [17]. Our common larch, like almost every other kind of tree, consists of numberless varieties, which differ considerably in quickness of growth, ultimate size, and value of timber. This subject has been much neglected. We are, however, on the eve of great improvements in arboriculture; the qualities and habits of varieties are just beginning to be studied. It is also found that the uniformity in each kind of wild growing plants called species, may be broken down by art or culture, and that when once a breach is made, there is almost no limit to disorder; the mele that ensues being nearly incapable of reduction.
- [18]. There is yet no sufficient data for the term alpine plant, but with reference to latitude. The influence on vegetables, arising from rarefaction and diminution of pressure of atmosphere, from difference of stimulus of solar ray—when the entire ray of light, heat, and chemical power, though less intense, is radiated fresh, and not much broken or modified by refraction and reflection, and heat communicated more in proportion by radiation than by contact of heated air; or from difference of electric or galvanic or other meteoric impression connected with altitude or ranges of mountains, or with primary rocks or more upright strata, has not been made the subject of research, at least has not been sufficiently investigated by any naturalist.
- [19]. When water is stationary, either in the pores of the soil or by itself, if the temperature be not very low, a slight putrefaction generally commences, aided by the dead vegetable or animal matter contained in the soil or the water; and it is only the more robust aquatic vegetables whose juices are not corrupted, from their roots being soaked in this tainted fluid. It would appear, too, that the aqueous part of the atmosphere is also susceptible of the same putrid changes, although in general the putrescency may have commenced before the evaporation. This condition of the aqueous part of the atmosphere is a disposing cause to blight or mildew in vegetables, and remittent, intermittent, and putrid fevers in man. Mill-ponds are notorious both for mildew and agues.
- [20]. We have had no experience of larch, excepting very young, growing on chalk and its affinities. We are told there are a few instances where larch has reached 50 years in these calcareous soils, some distance south of London. This merits attention.
- [21]. “Oh! the bonny blooming heather.”—“Man has spoken evil things of the sun, of love, and of life.”
- [22]. As we held this plan of forming larch knees, and of bending larch, of considerable importance, we some time ago presented it in manuscript, along with some other matter, to the Highland Society of Scotland. Tiring, however, of the delay of examination, perhaps unavoidable in their official departments, and from some improvements occurring to us during the delay, we requested it back. We now present it under this more convenient form to the Society, and hope they will find the examination or perusal of it printed, not quite so impracticable as when in manuscript. It will afford us pleasure to know that this useful Society approves, and that the members who have opportunity are setting about following our directions. We especially recommend to them to probe the roots of their growing larch, and to lay bare those fitted for knees.
- [23]. The landlord agriculturist is sufficiently aware of the influence of the baring the upper part of the root of turnip, while the plant is young, in extending the future growth of the bulb, and that a dry situation gives most root in proportion to stem. These are general laws in vegetation. There are few observers who have not remarked the very large size which roots have attained when the trees have originally been planted on dikes, and the dike earth removed, leaving the roots bare. Should any person examine the very great difference of thickness between the upper and lower part, from the heart of a root near the bulb, he will at once discover the influence of exposure to the air and freeness from pressure in promoting the swelling.
- [24]. As you ascend the tree the timber deteriorates greatly.
PART III. MISCELLANEOUS MATTER CONNECTED WITH NAVAL TIMBER.
NURSERIES.
Much of the luxuriance and size of timber depending upon the particular variety of the species, upon the treatment of the seed before sowing, and upon the treatment of the young plant, and as this fundamental subject is neither much attended to nor generally understood, we shall take it up ab initio.
The consequences are now being developed of our deplorable ignorance of, or inattention to, one of the most evident traits of natural history, that vegetables as well as animals are generally liable to an almost unlimited diversification, regulated by climate, soil, nourishment, and new commixture of already formed varieties. In those with which man is most intimate, and where his agency in throwing them from their natural locality and dispositions has brought out this power of diversification in stronger shades, it has been forced upon his notice, as in man himself, in the dog, horse, cow, sheep, poultry,—in the apple, {107} pear, plum, gooseberry, potato, pea, which sport in infinite varieties, differing considerably in size, colour, taste, firmness of texture, period of growth, almost in every recognisable quality. In all these kinds man is influencial in preventing deterioration, by careful selection of the largest or most valuable as breeders; but in timber trees the opposite course has been pursued. The large growing varieties being so long of coming to produce seed, that many plantations are cut down before they reach this maturity, the small growing and weakly varieties, known by early and extreme seeding, have been continually selected as reproductive stock, from the ease and conveniency with which their seed could be procured; and the husks of several kinds of these invariably kiln-dried[25], in order that the seeds might be the more easily extracted! May we, then, wonder that our plantations are occupied by a sickly short-lived puny race, incapable of supporting existence in situations where their own kind had formerly flourished—particularly evinced in the genus {108} Pinus, more particularly in the species Scots fir; so much inferior to those of Nature’s own rearing, where only the stronger, more hardy, soil-suited varieties can struggle forward to maturity and reproduction?
We say that the rural economist should pay as much regard to the breed or particular variety of his forest trees, as he does to that of his live stock of horses, cows, and sheep. That nurserymen should attest the variety of their timber plants, sowing no seeds but those gathered from the largest, most healthy, and luxuriant growing trees, abstaining from the seed of the prematurely productive, and also from that of the very aged and over-mature; as they, from animal analogy, may be expected to give an infirm progeny, subject to premature decay.
As, from many facts, a considerable influence is known to result in several vegetables from drying severely the seeds from whence they had sprung[26],—from exposure of these seeds to the sun and air,—from long keeping, or from injury by mould or {109} impure air, which all tend to shorten the life of the resulting individual, to accelerate the period of its seeding, and to increase its reproductiveness; the nurseryman should pay the utmost attention to the seeds he makes use of, procuring them as recent as possible, and preserving them in well-aired lofts, or under sheds, and also retaining them in the husks till the time of sowing: the superior germinating power of the seed thus treated will repay this attention.