Select Plants for Industrial Culture 



full oxide of iron red-brown dyes. As far back as 1823 a fluid extract 

 of Wattle-bark was shipped to London, fetching then the extraordinary 

 price of 50 per ton, one ton of bark yielding 4 cwt. of extract of 

 tar-consistence (Simmonds), thus saving much freight and cartage. 



Tan extract is best obtained from the bark by hydraulic pressure 

 and evaporation of the strong liquid thus obtained in wide pans under 

 steam-heat, or better still, to avoid any decomposition of the tannic 

 acid, by evaporation under a strong current of cold air. For cutch 

 or terra japonica the infusion is carefully evaporated by gentle heat. 

 The estimation of tannic acid in Acacia barks is effected most expe- 

 ditiously by filtering the aqueous decoction of the bark after cooling, 

 evaporating the solution and then re-dissolving the residue in alcohol 

 and determining the weight of the tannic principle obtained by 

 evaporating the filtered alcoholic solution to perfect dryness. 



The cultivation of the Black Wattle is extremely easy, being 

 effected by sowing either broadcast or in rows. Seeds can be obtained 

 in Melbourne at about 5s. per lb., which contains from 30,000 to 

 50,000 grains ; they are known to retain their vitality for several 

 years. For discrimination in mercantile transactions it may be noted, 

 that the seeds of the genuine A. decurrens are somewhat smaller, com- 

 paratively shorter, rounder and not so flat as those of A. dealbata, 

 while the funicular appendage does not extend so far along the seeds, 

 nor is the pod quite so broad ; from those of A. pycnantha they differ 

 in being shorter, thus more ovate than oblong. 



Seeds should be soaked in warm water before sowing. Any bare, 

 sterile, unutilized place might most remuneratively be sown with this 

 Wattle- Acacia; the return could be expected in from five to ten years. 

 Full-grown trees, which supply also the best quality, yield as much 

 as 1 cwt. of bark. Mr. J. Dickinson states, that he has seen 10 cwt. of 

 bark obtained from a single tree of gigantic dimensions at Southport. 

 A quarter of a ton of bark was obtained from one tree at Tambo 

 without stripping all the limbs. The height of this tree was 60 feet, 

 and the stem 2 feet in diameter. The rate of growth of the tree is 

 about 1 inch in diameter of stem annually. It is content with the 

 poorest and driest soil, although in more fertile ground it shows 

 greater celerity of growth. This Acacia is perhaps the most impor- 

 tant of all tan-yielding trees of the warm temperate zones, for its 

 strength in tannic acid, its rapidity of growth, its contenteduess with 

 almost any soil, the ease with which it can be reared and its early 

 yield of tanner's bark, and indeed also gum and stave-wood. This 

 tree is to be recommended for poor land, affected with sorrel. It is 

 hardier than Eucalyptus globulus, thus enduring the climate of South 

 England, although it hardly extends to sub-alpine elevations. 



The wood of this Acacia, particularly when the trees are in an 

 unhealthy state, is sometimes bored by the large larva of a moth, 

 namely that of Eudoxyla Eucalypti. 



For fuller information the " Report on Wattle-bark," presented in 

 1878 to the Parliament of Victoria by a special commission, may be 

 referred to. 



