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(a). Time of year for stripping.

Wattle-barks are often gathered all the year round, whereas they should only be stripped for three or four months in the year; (the months recommended are September, October, November, and December)note out of that season there is usually a depreciation of tannin in the bark. In these months, also, the sap usually rises without intermission, and the bark is easily removed from the tree. The impression appears to have prevailed amongst bark-strippers that whenever the bark would strip it possessed full tanning properties, but this is erroneous. After a few days of rain during other seasons of the year, a temporary flow of sap will cause the bark to be easily detached from the trunk, but then it is greatly inferior in quality. (Report Victorian Board).

Mr. A. L. Thrupp, in a paper read in March, 1890, before the Congress of Agricultural Bureaux in Adelaide, carefully warns tanners and others against receiving wattle-bark damp, pointing out that bark in that state engenders mould “of a most virulent form,” is liable to spontaneous combustion if stacked in the hold of a vessel, and, while bark received green will tan hides as fast as bark received dry, still, there is the undeniable fact, in nine cases out of ten, that leather produced from bark so received, so stacked, and used for tanning purposes is spotted, and therefore of second rate or third rate value.

Apart from the intermittent supply already alluded to, it is owing to the greedy and indiscriminating way in which wattle-bark has been gathered, and the moist condition in which it has often been shipped, that purchasers in England, finding the quality variable, have not entered into its regular employment as largely as might have been expected.

It should be purchased in the stick or bundle. “In this form its quality can be more readily judged; but when the supply of mature trees became diminished, nearly all the bark was chopped or ground prior to shipment, good and inferior being bagged together.”

Mr. Thrupp states that if the bark of a wattle-tree of three or four years be slit down on the south side with a sharp knife, from root to first branch. the increase in the bulk of the bark will be considerable. This has been tried in the Montacute District of South Australia successfuly for years. Spring is the proper time for this work. (Journal, South Australian Bureau of Agriculture, November, 1889.) A correspondent of mine, engaged in wattle cultivation in the Blue Mountains, has also practised this method with success. He has instituted comparative experiments, and is convinced of the advantage of the process in increasing bulk of bark. He performs the operation in the early winter (May or June).

The best wattle-barks contain comparatively little fibre. A good bark will, as a rule, grind to an impalpable powder, while one which with the same treatment forms a fibrous substance is, as a rule, to be avoided. I have not, however, come to any conclusion with respect to the connection between percentage of tannic acid and fibre.

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