On Naval Timber and Arboriculture. Patrick Matthew

On Naval Timber and Arboriculture - Patrick Matthew


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a sheltered morass, having the most numerously fibred, well extricated roots. In cases, where, from the moistness and coldness of the ground in early summer, there was a torpor of root suction, and, in consequence, the developing leaves withering up under an arid atmosphere, we have attempted to stimulate the root action by application of warm water, covering up the surface of the ground with dry litter to confine the heat; we have also endeavoured to encourage the root action by increasing the temperature of cold light-coloured soils, by strewing soot {39} on the surface for a yard or two around the plant, and by nearly covering a like distance by pieces of black trap rock, from three to six inches in diameter. The success from the pieces of trap appeared greatest; they diminished the evaporation from the ground, thence less loss of heat and of necessary moisture; and being at once very receptive of radiant caloric, and a good conductor, they quickly raised the temperature of the soil in the first half of the summer, when bodies, from the increasing power of the sun, are receiving much more heat by radiation than they are giving out by radiation.

      The oak should never be pruned severely, and this rule should be particularly observed when the tree is young. We have known several of the most intelligent gardener-foresters in Scotland err greatly in this; and, by exclusively pruning the oak plants, from misdirected care, throw them far behind the other kinds of timber with which they were mixed in planting. There is no other broad-leaved tree which we have seen suffer so much injury in its growth, by severe pruning, as the oak. The cause of this may be something of nervous susceptibility, or connected life, all the parts participating when one is injured; it may be owing to the tendency to putrescency of the sap-wood, or rather of the sap, the part around the section often decaying, especially {40} when the plant is not vigorous; or it may arise from some torpor or restricted connection of the roots, which, when robbed of their affiliated branch, do not readily forage or give their foraging to the support of the nearest remaining branch, or to the general top of the tree, but throw out a brush of twigs near the section.

      Although the oak often lingers in the growth while young, yet, after it attains to six inches or a foot in diameter, its progress is generally faster than most other kinds of hard wood, not appearing to suffer so much as others from excessive fruit-bearing. The value of the timber, and also of the bark, and the slight comparative injury occasioned to the under crop, whether of copse, grass, corn, or roots, independently of any patriotic motives, or religious reverence lingering in our sensorium from the time of the Druids, should give a preference to this tree for planting, wherever the soil and climate are suitable, over every other kind, with the exception of larch and willow, which, in particular soils, will pay better.

      The planter of oak should throw in a considerable proportion of Turkish oak into the more favourable soils and situations. The beautiful clustered, fretted foliage of this species gives a richness, and, in winter, when it retains the withered leaf, a warmth of colouring to our young plantations beyond any other {41} of our hardy trees and shrubs. We have had this kind, eighteen years old, equal in size to larches of the same age in the same ground. We cut down several of these oaks of about 8 inches in diameter, and compared the timber and bark with those of common oak of the same age. The timber was clean, very tough and flexible, with much flash, and we should suppose might suit for plank when matured; at any rate, from the splendid shew of the laminæ (flash), it would form beautiful pannelling and furniture. It shrunk, however, extremely while drying, which must have been partly owing to the quick growing and youngness, it thence consisting almost entirely of sap-wood, and this sap-wood almost entirely of sap; and, when left in the sun in the round state, after peeling, rent nearly to splinters—much more than the common oak under the same exposure. The bark was about double the thickness and weight of that of the common oak of equal size, and, in proportion to its weight, consisted much more of that cellular or granular substance most productive of tannin. The varieties of common oak with thick bark are generally of inferior quality of timber; but they are by far the finest, most luxuriant growing trees, with rich heavy foliage, and appear as giants standing in the same row with {42} the thin barked varieties, though planted at the same time.

      To the naturalist the oak is an object of peculiar interest, from the curious phenomena connected with the economy of numerous insects who depend upon it for existence. It would be tedious to describe the different apples, galls, excrescences, tufts, and other monstrosities which appear upon the oak. It is something like enchantment! These insects, merely by a puncture and the deposition of an egg, or drop of fluid, turning Nature from her law, and compelling the Genius of the Oak to construct of living organized oak matter, instead of leaves and twigs, fairy domes and temples, in which their embryo young may lie for a time enshrined.

      SPANISH CHESTNUTCastanea vulgaris, (Fagus Castanea, L.)

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      Spanish or sweet Chestnut, sometimes named Chestnut Oak, sometimes included in the genus Fagus, seems at least a connecting link between Quercus and Fagus. This valuable timber tree, the largest growing, and, in many places, also the most common in the south of Europe, and which was once so {43} abundant in England that many of the largest of our ancient piles are wooded of it, has been for several ages much on the decrease in this country; owing, probably, to a slight refrigeration of climate, which, during this period, appears to have taken place, preventing the ripening of the seed, or, in more rigorous winters, following damp, cold summers, destroying all the young plants (at least the part above ground), whose succulent unripened shoots and more delicate general constitution, from immatured annual round of life, or imperfect concoction of juices, have not power to withstand the severe cold sometimes occurring near the surface of the earth. A very general destruction of the young plants of this kind of tree has occurred more than once within our memory from severe frost; but as the climate, a few years back, rather improved, and the spirit of planting became more general, a considerable number of plants of this tree have attained height and hardihood to withstand the cold, excepting in the points of the annual shoot, which we notice are again nipped (year 1830). This may give encouragement to more extended planting, as the tree is handsome, and, in most places, where water does not abound nor stagnate, acquires great size in comparatively short time. It is said to prefer a gravelly or stone {44} rubble subsoil, but we have seen it in rich clay, in row with large beeches, even exceed them in size. We should prefer for it any deep friable dry soil.

      There is one circumstance connected with this timber in this country, at least in Scotland, which must prevent its general use in ship plank, and be of material injury to it for ship timbers; this is, that few trees of it of size are found without the timber being shaky or split, some to such a degree that the annual rings or concentric growths have separated from each other. This appears to be owing to our climate being colder than what is suitable to the nature of the plant; the sap in the stem possibly freezing in severe weather and splitting, or severing the growths of the timber, but more probably occasioned by the season being too short, and too moist and cold, to ripen or fill up with dense matter, sufficiently, the frame of the annual growths; thence, as each ring of sap-wood, prematurely hastened by the torpor of moisture and cold, turns to red or matured wood, and, in so doing, dries considerably within the other rings of moist sap-wood, the contractile force may be sufficient to separate this growth from the next external sap growth, the cohesion existing between the tissue or fabric of the growth being much stronger than the cohesion between one {45} growth and another. The uncommon dryness of the matured wood, and moistness of the sap-wood of this tree, and smallness of the number of sap-wood rings, commonly only from 2 to 6 in this country, incline us to believe that this is the cause of the insufficiency or defect; and that, in a milder, drier climate, the sap-wood rings will be found to be more numerous, and thus, independent of a better first ripening, affording a longer time for their cells to be more filled up with an unctuous matter (which prevents the shrinking) gradually deposited while they convey the sap, the sap-wood rings being the part of the timber through which the sap circulates. As proof of this unctuous deposit or filling up, we observe that dry sap-wood imbibes moisture much quicker, and in greater quantity, than dry mature. We think this premature maturity (if we may so term it) of timber in cold countries, a general law. Our larch, originally from the Apennine, has not more than one-third of the number


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