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Pine Scrub and Pine-thinning.

C. robusta mainly forms the Pine Scrub of the west; to a less extent C.calcarata is a pest; sometimes, in a given area, the two species are commingled. The matter of dealing with these lands is discussed in a valuable pamphletnote I do not, therefore, propose to do more than briefly touch upon the subject.

"Pine Scrub" is a serious pest to pastoralists in the interior, the land not only being rendered useless for grazing purposes by reason of the millions of young trees, as thick as a maize-crop, but this scrub is a safe hiding-place for innumerable vermin-rabbits, dingoes, &c. Efforts have been made, under the supervision of the Forest Department, to thin out the saplings, and thus allow trees to attain maturity.

The following extract from a report by Cadet Swain, of the Forest Department, which was obtained at my instigation, gives so excellent an account of White Pine, the principal component of Pine Scrub, that I reproduce it here. Mr. Swain was in the Grenfell, &c., district:—

A symmetrical tree attaining a height of 100 feet, of glaucous foliage, and often crowded branches. It occurs generally as Pine Scrub, with a sprinkling of matured trees; on reddish sandy loam in almost pure forest, with a slight admixture of White and Yellow Box and Kurrajong.

It is a light-demander, and though the scrub is often very thick, the foliage is so thin that the sun obtains apparently unrestricted admission.

Reproduction is effected at long irregular intervals as the result of a good season, when the young pine scrub quickly covers the ground with a glaucous seedling growth. The " thicket " stage succeeds — a dense crop of whipstick pine with dead snaky branches interlacing and forming the dreaded pine scrub. This is followed by the pole stage.

A further report says:—

In some places the scrub is so dense that it is impassable, and I have counted twenty-six pine plants, each from 3 to 8 feet in height, upon 1 square yard. Plants growing as close as this can never reach maturity or usefulness. I have lately supervised the thinning out of a small area (120 acres) in the Weddin Forest Reserve and have left all those of 4 inches and upwards intact, and thinned out those


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under this size to 8 feet apart, which I think is quite close enough to enable them to become useful. The pine is occasionally attacked by a grub, which is about 7/8 ths of an inch long, of a white or cream colour. Its head is the largest part and it burrows around the stem of the plant, just under the bark, while young, and afterwards penetrates to the interior, sometimes killing the tree, but so far does not seem to have destroyed many in this district; but rabbits, if hard pressed for food, will bark the small saplings, as has been done in this district, but not to any great extent, as the rabbits are not at present numerous enough. — (Forester Postlethwaite, Grenfell.)

In the Annual Report, Forest Branch, Department of Mines, for 1884, p. 35, is a "Report by Dr. von Lendenfeld on the life-history of an insect destroying the pine scrub in the Nymagee, Condobolin, and Forbes districts." The insect in question is a beetle Diodoxus erythrurus, White, which ringbarks the young pine scrub. He made the remarkable proposal that these beetles should be systematically introduced into the pine scrub in order that they might clear it, saving the cost of felling or ringbarking. The larval stage of the beetle is the grub already alluded to by Mr. Forester Postlethwaite. While there are, of course, drawbacks to pine scrubs, yet the pine is a valuable asset in this country, and the time may come when it will be carefulIy conserved. Already in parts of the country the scarcity of this valuable timber is being felt, and it often grows in situations entirely unsuited to agriculture, or even pasture.

There is a very limited quantity of matured pine-trees in my district; the young trees vary in size from 2 to 10 inches in diameter, and are of healthy condition and straight, but are of such dense growth that the trees can make but little headway on account of not having sufficient light and moisture. — (Forester Payten, Corowa.) I consider we have a supply of pine here which, with care, would last a generation if our reserves are only attended to-that is, by having the timber judiciously thinned out and the useless scrub destroyed. — (Forester Condell, Narrandera.) Between the Murray and the Darling there must be at least 50,000,000 acres of pine country, less what has been destroyed. In all that area there are no other timber of any commercial value but Pine and River Gum (Eucalyptus rostrata). The pine derives its principal value from its resisting the white ants and because there is no other timber, west of Forbes, in any quantity that does so. The notable increase and spread of young pine-trees dates back from the country being stocked with sheep; after rain, the seed is dibbled into the soil by the sheep's feet. From 20 miles north of the Murrumbidgee to beyond Cobar, and from Dubbo, Forbes, and Wagga, on the east, to Booligal and Mossgiel, on the west, may be considered a vast pine forest with a few open plains intervening. In my belief a great misapprehension exists regarding the time required for a pine sapling to become a matured tree-say from 1 foot high to 15 inches in diameter. Mr. J. Ednie Brown thought it would grow to be 1 foot thick in twelve or fourteen years. I think it will take at least sixty years; and this is accounted for by the diminished and intermittent rainfall of the Western district. I have counted eight young pines, 3 to 8 feet high, on 14 square inches. As they grow up the taller kill the shorter ones, while the density or number of the plants wither the lateral branches, ultimately leaving the trees that matured without branches or knots for 20 feet to 25 feet from the ground. But for the pine the whole of the Western district would require to import its timber, for American or Baltic is ruined by the white ants in a year or two. — (Forester Kidston, Condobolin.) In places where young whipstick pine is growing thickly I have seen a few trees, about 4 feet high, that have been cleared and pruned, the consequence being that in seven years they have become saplings 18 feet high, with a circumference of 1 foot; whilst on the other hand, whipstick pine left alone, growing some distance from Gunnedah, is, I am credibly informed, almost the same to-day as it was fifteen years ago, the only dlifference being that some are taller than others, perhaps 14 feet high, but with no trunk of any size; but if these were cleared and pruned now they should in a very few years mature, and the gradual dying out of the matured pine in my district without a corresponding increase, or anything being done to push the young pine forward, should show the necessity of fostering an important industry. — (Forester Harris, Gunnedah.)
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