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The Waste of our Timber, and how to avoid it.
By A. RUDDER,
The purpose of this paper is to direet attention to the, too often, great waste of timber caused by the manner of its use, and to point out how this might and should be avoided, more especially in connection with the construction of culverts and bridges, as now generally practised, often for want of a little more care and forethought or judgment and practical experience; and to give a few hints on this subject. Before proceeding, however, with what I have to say, I propose, first, to give a brief descriptive account of some of the more important timbers of our Northern Coast country (of which I have bad some sixty years' experience), and will direct attention to what I consider are most suitable for use in the kind of work referred to, and to some others which, in my opinion, should be carefully avoided.
Grey Ironbark (Eu. paniculata, Smith).- Perhaps of all our hardwoods, on account of its great strength and durability, and comparative freedom from defects, may be justly considered to rank first, more especially in its use as piles (where there is no cobra) and girders, and railway sleepers, or in the construction of all bridge work, or wherever great tranverse strength is required, but it has the disadvantage of being very combustible, and is subject to the ravages of white ants (termites). This timber differs a good deal in quality, according to soil and situation, the best and soundest trees, and the largest, being usually found in somewhat scrubby places. In colour it varies from grey to shades of a yellowish colour, or light red, and very dark brown, when green, but these colours change in drying, sometimes becoming, Where dark, much paler, and in the case of pale red or grey, becoming of darker colour. Unfortunately, this timber is not very plentiful, but in this district and some others it shows, in places, a readiness to reproduce itself, and the young growth is generally very promising.
Red Ironbark (Eu. siderophloia, Bentbam). This tree may be distinguished from the grey ironbark by its broåder leaves and larger fruit, and, generally, looser and more flaky bark, with wider fissures or striate channels than is common with the grey variety. It is also of more gregarious babit, and prefers low clayey flats and stony ridges, and the mature trees are generally pipy, and the colour of the wood is red. The timber of this ironbark is strong, hard, dense, and heavy, but in lasting quality is not always reliable, as I have repeatedly seen it quite rotten after ten or fifteen years, but this is not usual. t is very plentiful in places, in the Clarence River district in particular, but in these parts the timber is of inferior quality, especially on the ridges, where the trees are stunted and badly grown. For railway sleepers this timber is fairly good, but is scarcely to be recommended in the
round, not as a rule, for bridge work, as its contral heart wood is not reliable, and it is very subject to the white ant, more so than any other hardwood I know of.
Narrow-leaved Ironbark (Eu, crebra, F.v.M.) is a much smaller tree than either of those mentioned, and, as far as I have seen, is of spreading and somewhat drooping habit. Leaves very narrow, fruit and flowers very small. Timber in colour, when fresh, either red or dark brown. Is strong and lasting, and suitable for railway sleepers and girders, &c., and for use in bridges and culverts generally, where long lengths are not required. It does not, as a rule, approach so near the coast as the grey and red varieties. I have seen a little of it near Clarence Town, and it is fairly plentiful on the tributaries of the Upper Hunter.
Grey Gum (Eu. punctata, var. grandiflora).—This is one of two trees with the same vernacular. In general appearance, to the casual observer, the trees are much alike, but the leaves of this are rather broader, and its fruit and blossons are very much larger than those of the other variety, and the trees generally are not so large, and are more limited in range of habitat, and, as a rule, do not approach so near to the coast, though I have seen it at Raymond Terrace, and near the beach at Charlotte Bay and Wallis Lake in this district, the two trees often grow together. I have mostly observed it on the lower ranges in the counties of Gloucester and Durham. The timber is red in colour, is hard, and very lasting, and is well suited, in the round, for heavy timbers in bridges and culverts.
Common Grey Gum (Eu, propinqua, Dean et Maiden).-This tree occupies a wide range of our Northern Coast country, and is very plentiful in the county of Gloucester. Its bark is deciduous, of grey colour, with a somewhat loose crumbly surface ; leaves falcate, are somewhat narrow, often with a bronze-like or copperish coloured tinge. Fruit small, and blossom buds dome-shaped. The wood of this tree is red in colour, is hard, heavy, and dense, and is very lasting in the ground, and is very suitable for all round heavy timbers for culverts and bridges, and for posts and rails, and is also, I believe, excellent for railway sleepers, though not, as yet, much used for this purpose by the Railway Department, for want, I believe, of a true knowledge of its qualities, and owing to its confusion with other kinds of trees with the same vernacular whose timbers are inferior. It is less liable to the ravages of white ants than ironbark, and is, I believe, more lasting in the ground. For sawn stuff it is not a favourite at the mills, as it is somewhat liable to concentric rings and grub holes. This grey gum, strange as it may seem, though very abundant, and one of the most distinct in its characteristics, which rarely varies, until quite lately I could not ascertain that it had received any botanical definition, although I had often endeavoured to bring it, and its timber, into more notice, and had repeatedly sent specimens of its leaves and flowers and fruit to some of our leading botanists, who never satisfied my queries. I also repeatedly sent specimens, including its wood, to the Forest Department, when at last, after calling special attention to it, the matter was taken in hand by the Government Botanist, Mr. Maiden, a very careful, intelligent, and painstaking investigator, with the result, as I have just seen for the first time, tbat it has now received its designation in connection with his own name as above.
Spotted Gum (Eu. maculata, Hooke).-This timber is of doubtful durability in the ground, but is tough, strong, and elastic, and of much value for waggon and coach-building and in house work generally, for sleepers excepted. It makes excellent flooring boards and lining, and as some of it has nice figures, it might often be used for many purposes in cabinet work, and is excellent for axe handles, but its sapwood must in all circumstances be avoided, as it is very perishable. This, and the tendency of this timber to rings and star shakes, are its principal defects. Except, perhaps, for flooring, or in the absence of other timbers, it should be avoided for all bridge work
Red Gum (Eu. tereticornis, Smith).–Usually found growing on river and other flats, and, in some places, on mountain slopes more inland. Of this tree there are several kinds, which are often mixed together, and are very similar in general appearance. Of those with the larger and broader leaves, their timber is often next to worthless, whilst that of the very narrow-leaved variety, the wood of which is of a rather lighter red in colour than the other, is inlocked, harder, and is very lasting both in and out of the ground. This timber might be highly recommended for use in bridges and culverts but for this danger, that the inferior kinds, of which their woods are very similar in appearance, might be mistaken for it, or used wrongfully by unprincipled contractors. Of this narrow-leaved kind I have now before me part of a fence post which I took out of the ground in May last, from where it had been for over fifty years, and is now quite fresh looking and tough, and sound as ever.
Flooded Gum (Eu. saligna, Smith).--This is a large tree, often up to 7 or 8 feet in diameter, with smooth deciduous bark of a silvery grey or white in colour, excepting near the butt, where it is usually for some distance up from the ground, rough, of dark colour, and persistent. This tree is generally found growing on the alluvial banks of rivers and creeks, or in dense scrubby mountain dells. The timber, in the young trees especially, is often soft, spongy, and brittle near the heart, and in such case, it is next to worthless, but in old and mature trees, in which the centre heart wood has rotted away, leaving them hollow, their timber, especially that of the butt logs, is tough and strong, and becomes very hard when dry, and is suitable for ship's planking and for building purposes generally, also for fence rails, &c., but for bridge work it is not, taken altogether, very reliable.
Blue Gum (Eu, saligna).-Is very similar, in general appearance, to the above, and is often found with it, but the trees are not usually so large, and their bark has a bluish colour, and is somewhat blotchy in appearance, and is rarely rough and persistent at the butt, and the wood is usually redder. The timber of this tree differs a good deal in character and quality from very tough and inlocked to soft, brittle, and fissile (leaving a doubt in my mind whether there are not several kinds). This is often a good timber for building purposes generally, but in some places the trees are pipy, and the wood is subject to grub holes, and is not lasting in the ground, and should not be used in any bridges where better timbers for the purpose are obtainable. Blue gum is frequently met with on open country on the mountains east of the Dividing Range, and is very plentiful on the Upper Patterson, Allen, and Williams rivers, &c.
Red Mahogany (Eu, resinifera, Smith).-Is a large tree up to 4 or 5 feet or more in diameter, with stringy or fibrous bark. The wood is rather soft when green, but becomes hard and tough when dry, does not warp, seasons quickly, works up well, and takes a good polish, is good for almost all house building purposes, makes the best of shingles, and, as it does not affect the water, should be used when slabbing for wells is required. It looks very well as skirting boards and bannister rails, &c, and lasts fairly well in tbe ground, and is not much subject either to white ants or cobra. Though not a favourite with cobra or white ants, it is not proof against either, though they prefer many other kinds of timber. For fence rails it is very lasting, of which I have proof in part of a rail now by me, which has been exposed to all weathers for about forty-five years. This timber is still fairly plentiful in places along some of the northern coast country, but is now so much in request that it is likely to become scarce before long. As I have done before, I would advise a trial of it for wine casks, for which, I believe, if selected free from pin-holes, it will be found suitable.
White Mahogany (Eu. triantha, Link).-In brushy places this tree attains to a considerable size up to 5 feet in diameter, but in the open it is usually smaller. It is one of our stringy-barks, and is fairly plentiful along the northern coast country. The wood of this tree is hard, and very close in the grain, but splits easily, and is very similar in appearance to that of tallow-wood. The principal defects of this timber are a tendency to rings and pin-holes. For lasting in the ground, as far as I know, it has no equal. I have seen fence posts of it quite sound after being in use for over fifty years.
Tallow-wood (Eu. microcorys, F. v. Mueller).—This fine timber is so well known that I need say but little about it. One of our stringy-barks it is a tree of exceptionally large size, up to 25 feet in circumference by 180 to 200 feeet in height. (Of twenty-five trees I measured at 4 feet from the ground, the average circumference proved to be 17 feet 2 inches.) The timber of this tree is strong and durable, and is oleaginous, so that it retains a certain degree of moisture, and consequently shrinks less than our other timbers, but takes a long time to season. In colour it varies in shades of yellow to pinkish occasionally, when found growing in moist scrubby places. I have seen this tree lying on the ground in damp shady places, with the bark on, for many years, to find it always as fresh looking and moist, or more so, as in the growing tree.
Blackbutt (Eu, pilularis, Smith).-This is a half bark; a large tree of rapid growth. The timber of this tree, which is of a whitish or straw colour, is more or less subject to gum veins and is fissile, but for all that is a good all round timber for general house-building purposes, but it differs a good deal in quality, and is very subject to the white ants, for which reason, and its tendency to split, it is not suitable for use in culverts, and bridges, unless for planking. Of all our trees this perhaps shows the greatest tendency to re-afforest, where the soil is suitable; and is of special value on this account.
Turpentine (Syncarpia aurifolia, Tenore).-Is a large tree, fairly plentiful; is found occasionally in the open, but more generally, and of larger size in undulating scrubby forest; and in scrubby gullies in and near coast country, and east of the dividing range. The best quality is that on the scrubby ridges. In colour the wood varies from red to dark brown, and is occasionally vellowish, and some of it is prettily marked. It is much used for piles, also for the bottom of droghers and punts, on account of its being considered impervious to the cobra, but in this respect, in some instances, it has been found to fail, hence it is supposed by some there are two kinds, but of this we have no proof. The darker-wooded trees are, I think, trees a little past their prime, the wood of wbich has often shades of colour, probably indicating incipient decay. The anti cobra element in this tree seems to be a sort of non-drying glutinous gum in the liber, which exudes when it is cut through in golden beads, and is very attractive to the native bees. The timber of this tree is fairly lasting, but is apt to rend and warp a good deal, as sawn stuff, in the seasoning, but this, so I am informed, is entirely obviated by a few weeks soakage in water, and I have seen it after this treatment free from cracks. It steams remarkably well, so much so, that I have observed stout planking successfully turned edgeways at an
angle of over 30 degrees. I believe this timber might be used to advantage in cabinet work, as some of it is handsome, and takes a good polish, and only, I believe, requires proper treatment to make it more highly esteemed for many purposes.
Brush Box (Tristania conferta, R. Brown).—This tree, locally known as woollybutt, also as brush box on the north coast country, is of large size, not unfrequently up to 17 and 18 feet in circumference (of eighteen trees I measured their average girth was 17 feet 4 inches) has not, on account of its large size and great quantity, in accessible places, received anything like the attention it deserves, especially as the trees are generally quite sound a little up from the ground. I can recollect this timber in the earlier days, over fifty years ago, as the chosen of all others by a firm of ship-builders of the names of Malcome, Newton, and Ferrier, who used it for ships planking. It becomes pale when dry, and in texture is fine and close in the grain, and is usually inlocked, and, when seasoned, stands more friction than any timber I know of, not excepting the best ironbark, and for this reason is used for tramway rails, also for bullock-yokes and planes, as it works very smooth. I have seen it used in decking for bridges, of which there is now an example in a bridge at Gooloogalook, in this district, where it has been placed for esperiment side by side with tallow-wood, with the result, so far, after four and a half years, with the exception of two planks, one of which seems to be in part sapwood, and the other too near to the heart, that it is wearing well, even better as regards friction, than the other timber. Unfortunately, it shrinks unevenly, and in thin stuff is given to warp, but perhaps by soakage in water these defects might be remedied. In the house in which I am now writing one of the floors is of this wood, which has been down for twenty-seven years, and is still in excellent order. I believe this timber will be found of
given to it.
Bloodwood (Eu. corymlosa, Smith).-Is a tree of considerable size, and is plentiful in places on and near the coast country. In colour its timber is red, and is very subject to gum veins and rings, on which account its appearance is not reassuring, but, so long as the concentric rings are not detached, and it is of fairly good quality. It is very lasting in the ground, and is not apt to warp or rend in seasoning, and is excellent for fence-posts and sleepers, and wherever round timber is required for use in culverts and bridges and for ballast logs, and for ground work generally, is in my opinion, not to be surpassed, as it is as lasting, and not so combustible, or subject to the white ant, as ironbark. For fuel for furnaces it generates more heat than any wood I know of.
Swamp Mahogany (Eu. robusta, Smith).—As its name implies, this tree grows on swampy lands. Something like bloodwood in character, its timber is more or less subject to gum-veins, and, on this account, is not suitable for sawn stuff. As round timber, especially in wet ground, and also for ballast logs, if of good quality, it is very lasting, and suitable for use in bridges and
very like that of red mahogany.
Peppermint (Eu, piperita, Smith).-Sometimes called white stringy bark. This timber often attains to large size. The wood is soft, and subject to gum-veins, and shrinks, and cracks a good deal in the seasoning, and is not lasting, and should be avoided in all public works. If properly seasoned, however, it may be used for flooring boards and other purposes under cover where better timber is not to be had. Is distributed on low-lying lands and mountain districts near the coast.