Dyes and Tans. 



420 



[November, 1908. 



have not practised cultivation of the 

 wattle tree to the same extent as the 

 Natal growers, though recently in- 

 creased attention has been given to the 

 formation of wattle plantations in Aus- 

 tralia (this Bulletin, 1807, 5, 187). 



As already indicated, the black wattle 

 is the species usually selected for plant- 

 ing, and the following information re- 

 garding the cultivation of the tree and 

 the preparation of the bark relates more 

 especially to this species. 



Cultivation. 



Although the black wattle will grow 

 in practically any kind of soil, expe- 

 rience has shown that a friable sandy 

 loam, or a sandy soil lying on a clay sub- 

 soil two or three feet below the surface 

 answers best. The roots do not pene- 

 trate deeply into the ground, and con- 

 sequently soil which retains moisture 

 is advantageous for their culture. 



The plants are invariably grown from 

 seed, but no special precautious are 

 necessary for the sowing. As a rule, 

 rows about 12 feet apart are prepared, 

 and the seed, mixed with a quantity 

 of sand, is planted about one inch deep 

 and in such a manner that the young 

 trees can eventually be thinned out to 6 

 feet apart in the rows. 



The outer covering of the seeds is ex- 

 tremely hard, and to assist germination 

 the seeds should be specially treated 

 before sowing, as under ordinary circum- 

 stances they may remain in the ground 

 for a considerable time without germi- 

 nating. More rapid germination can be 

 brought about in a number of ways. 

 Perhaps the commonest practice is to 

 cover the seed with boiling water, in 

 which, after cooling, they are allowed 

 to soak for about 24 hours, after which 

 they are sown as soon as possible, im- 

 mediately after removal from the 

 water. In Australia the seeds are fre- 

 quently roasted, but care has to be 

 taken to avoid loss by over-heating. 

 Quite recently excellent results are said 

 to have obtained in German East 

 Africa by soaking the seeds in concen- 

 trated sulphuric acid and keeping the 

 mixture stirred occasionally to prevent 

 caking. After the lapse of four or five 

 hours the seeds are removed and 

 thoroughly washed in running water, 

 when they are ready for setting. It is 

 stated that after this treatment 80 to 90 

 per cent, of the seeds germinate in a 

 tew days. 



Indian corn (maize) is frequently grown 

 in the spaces between the young plants, 

 generally two rows of maize between 



each two rows of wattles, and this 

 serves to provide a return from the 

 plantation whilst the wattles are matur- 

 ing. 



After germination the plant grows 

 quickly, and at an age of only four years 

 it generally attains a height of from 25 

 to 30 feet. The foliage is luxuriant and 

 affords luxuriant shade for animals or 

 low-growing crops. Practically no atten- 

 tion is given to the trees themselves, 

 for if they have been properly distri- 

 buted pruning is unnecessary and several 

 crops of wattles may be taken off the 

 same soil without rendering it unsuitable 

 for their further cultivation. 



One of the most serious enemies of the 

 wattle grower is fire, which sometimes 

 spreads from the surrounding prairie 

 and destroys the plantations unless fire 

 ''breaks" have been constructed by 

 ploughing broad strips of land round 

 the plantations. 



Several insect pests have also made 

 themselves felt on Natal Avattle estates, 

 the chief of these being a bagworm 

 which destroys the foliage and thus 

 checks growth, and red and white ants 

 which destroy the roots. Locusts are 

 also a serious trouble in some years in 

 Natal, but with suitable precautions 

 their depredations may to a certain 

 extent be mitigated. 



Wattle trees reach their prime in 

 about ten years from the time of sowing, 

 though many trees are marked down as 

 large enough to strip after seven or even 

 five years. The rate of growth varies in 

 different localities and soils, and indivi- 

 dual variations in the seed also exert 

 considerable influence. Wheu an area 

 of foiests is old enough harvesting of 

 the bark is commenced. In Australia 

 the trees are usually stripped during 

 three or four months of the year (gener- 

 ally September, October, November, and 

 December), but in Natal the work is 

 carried on at all seasons, a$ the barks 

 strip readily except in very dry weather. 

 Nevertheless the period from the begin- 

 ning of March to the end of April is 

 generally adopted, despite the danger 

 of getting the stripped bark soaked 

 with rain before it can be brought under 

 cover and thus losing part of the tannin. 



Attention has been drawn recently to 

 the possibility of variation of the con- 

 tent of tannin being caused by stripping 

 at different times of the year, and this 

 matter is beine investigated (this Bulle- 

 tin, 1908, 6, 86). 



After clearing away the dead twigs 

 and leaves at the bottom of the tree an 

 incision is made in the bark either (a) 3 



