Vol. XII. No. 282, 



THE AGRICULTURAL NEWS. 



03 



WATTLE BARK. 



I 



In view of the fact that the plants yielding wattle bark, 

 which gives an extract rich in tannin that is used largely in 

 the leather industry, may possibly become eventually of 

 practical interest in the West Indies, it has been thought 

 useful to present, in this and the next two numbers of the 

 AgricuHiiinl Neii:<, a few notes on these' plants, dealing par- 

 ticularly with their nature, habitat, cultivation, yield and 

 exploitation. 



ORIGIN*. A recent publication (A^/ric. Jotirn. Union 

 of South A/'riiM, TV, 0, 6G7) states thit, of the acacias tried 

 in South Africa, only the following were found to contain 

 sufticient tannin to make them of economic importance: black 

 wattle (Arai:i(j, decunens, var. mollis), green wattle (A decur- 

 rens, var. nwinalis, golden wattle {A. jii/cnantha). In stating 

 this, it may be mentioned that the wattle barks are dealt 

 with in Baron von Mullers Select Ej.ti-aTropical Plants. 



The name wattle is derived from the Anglo Saxon tvatel 

 or waful, meaning a hurdle. The wattles of England are the 

 twigs of the osier (Sali.c viniinalis ). 



HABITAT OF WATTLE PLANT.S. An article in the Journ. 

 Agric. Dept. Victoria, X, 11., 684 (November 1912), 

 gives the habitat of A. decurrens as New South Wales, 

 Victoria and Queensland, and of ^1. pi/cnantha as Victoria, 

 New South Wales and South .\ustralia; this fact regarding 

 the latter plant indicates that it should do well in subtropical 

 or warm-temperate regions. The plants have been introduced 

 into India, among other countries, especially in the Nilgiri 

 Hills (in 1840) according to Sir George Watt (Commercial 

 Products of India, p. 2), where the climate is warm- temperate; 

 here, the two species mentioned are partly cultivated and 

 partly wild {Mnnual of Indian TivtlKvs, Gamble, p. 291). 

 The story of the introduction of these Australian plants into 

 Natal is told shortly in Agric. ./onrh Union of South 

 Africa, IV, 5, 666 (November 11U2), the first black wattle 

 seeds having been planted there in 1864. As is shown in 

 Agric. Joiirn. Cape of Good Hope, XXV, .3, 277, the 

 black wattle has been grown successfully in Cape Colony, 

 where the rainfall is sutticient or there is irrigation. New 

 Zealand is another country where the black wattle has been 

 tried on an extensive scale; in 1904, there were more than 

 4, .500 acres of artificial plantations of the tree in this 

 dominion ((Queensland Agric. Journ. XV, .5, 730). The 

 plants have also been introduced into Ceylon. In the 

 Briti.sh East Africa Protectorate and German East Africa the 

 cultivation of the wattles has passed the experimental stage, 

 and is successful. 



SEEDS. Watt, in the Dictionary of Economic Products of 

 India, states that I H). of the seeds of the black wattle con- 

 tains 30,000 to .jO,000 grains, and that (according to MuUer) 

 this quantity could be obtained in Melbourne at a cost of about 

 five shillings. Jlessrs. Dammanii .t Co., of San Giovanni 

 a Teduccio, near Naples, advertise seeds of A. decurrens at 

 od. jier oz. or 3s. 2d. per lb., and of A. pycnantha at id. per 

 oz. or 3s. per Bj. A description (.Tourn. Dept. Agric. Victoria, 

 X, 11, 688) of germination experiments with air-dried seeds 



of various acacias shows that those of A. decurrens main- 

 tain their vitality for a long time: 63 per cent, germinated 

 in a sample that had been kept for seventeen years. As the 

 seeds, like those of many leguminous plant.s, are very hard, 

 they are often softened before they are sown, preferably 

 by dropping them into water that has just been boiled and 

 allowing them to remain until it has cooled; in this case the 

 seeds must be planted at once. Other methods suggested in 

 thi' journal just mentioned are soaking in concentrated sulphu- 

 ric acid for one to six hours and then washing well in water 

 and limewater, and filing the seed. It is recommended by 

 the same authority that, in any case, the seeds should be tested 

 by soaking a few of them in water, for two or three days, and 

 noting the proportion that swell. If only about 10 per cent. 

 of them remain hard, it is not worth while to treat them before 

 sowing, as a comparatively small proportion will fail to ger- 

 minate because they have not been able to absorb water. 



It may be mentioned that the seeds of A. pycnantha 

 have a special interest on account of an investigation (Proc. 

 Linn. Soc. N'ew South Wales, X.XXIH, 4, 801) which showed 

 that 4.5 per cent, of the nitrogen in them is non-proteid 

 nitrogen, and led the author to conclude that the importance 

 of non-proteid nitrogen to plants is not properly recognized. 



sowiNo THE SEED. Tile following hints are taken from 

 the journal published in Victoria, mentioned above: — 



'Sowing seeds broadcast on ploughed or burnt land 

 involves a considerable waste of seed, and is not always 

 satisfactory in its results. Planting seedlings or individual 

 seeds appears at first a more expensive and troublesome way 

 of establishing a plantation, but is in the long run more 

 satisfactory in its results, and enables the plants to be spaced 

 out the proper distance apart without any subsequent 

 thinning being necessary. If, however, the seedlings are 

 grown in masses in trays, they are apt to suffer when planted 

 owing to the disturbance of their roots. On the other hand, 

 growing singly in pots in the ordinary way means consider- 

 able expense. For raising seedling trees on a large scale, 

 the Forests Department uses a very cheap ingenious and 

 indestructible pot. This consists of a strip of thin metal 

 (tin, zinc, or galvanized iron may be used) .something like an 

 ordinary collar, Imt shorter and broader, and with the free 

 ends bent over, one inwards and one outwards, so as to 

 form an interlocking flange. When bent round and the 

 flange interlocked, it forms a tlower-pot with sloping sides 

 but no bottom. As it stands on a slab no bottom is neces- 

 sary, and by the time the seedlings are large enough to plant 

 out the roots have bound the soil in the pot together. 

 When planting, a little lateral pressure unlocks the flanges, 

 the strip of metal unrolls, and the roots, with the soil around 

 them, can be planted with a minimum of distuib.ince. 

 Another method is to raise seedlings in short lengths of 

 bamboos filled with soil, simply splitting the bamboo and 

 planting the whole in the soil when the seedling is old 

 enough. The tubes should be 4 to 6 inches long, and 

 hollow throughout. If the tube is already soft, it need not 

 be split before planting. Where preferred, however, plant- 

 ations may be established by broadcasting the .seed.' 



It should be mentioned that the article from which this 

 quotation is taken is the first (November 1912) in a series, 

 by Professor A. J. Ewart, of Melbourne I'niversity, appear- 

 ing in the -lournal of the Departimnt of Agriculture of 

 Victoria, and although this is the only one that has been 

 received so far, it may be concluded that the whole series 

 will be worthy of the attention of those interested in the 

 wattle barks. 



As has been indicated, this subject will be continued in 

 the next number of the A'iri<ultural Jfews. 



