39 



Amongst the evidence received by this Com- 

 mittee was that of Mr. A. C. Macdonald (1891 

 b), who reviewed the question oi: "Prickly-pear 

 in South Africa, and made a number of sugges- 

 tions to the Government with regard to its eradi- 

 cation (pp. 34 and 35), most of these being sup- 

 ported by the Secretary for Agriculture 

 (Fischer, 1891, pp. 42-3). 



In 1898 another Select Committee made its 

 report (R.S.C., 1898). The serious economic re- 

 sults of the spread of the pest, which have been 

 referred to earlier, are again emphasised. It 

 was considered that " compulsory legislation for 

 the eradication of the weed was not desirable, 

 but that the free supply of scrub exterminator 

 by the Government would be the most effectual 

 means of attaining the object sought." 



A much longer report was furnished by the 

 Select Committee appointed in 1906 (R.S.C., 

 1906) . After reiterating the effect of the spread 

 of Prickly-pear on the general community, and 

 drawing attention to the seriousness of the pres- 

 ence of the jointed cactus, the report goes on to 

 state that the Committee was of opinion that the 

 State should now assist the private individual to 

 exterminate both of these pests. Though com- 

 pulsory eradication alone was considered unde- 

 sirable, it was believed that " a system of obli- 

 gatory cleansing coupled with graduated State 

 aid and encouragement would bring about the 

 desired result." It was suggested that every 

 farmer troubled with the pesf should clear his 

 land within a reasonable period, and, after pro- 

 ducing a verified statement of the cost, should 

 be reimbursed according to a scale, the following 

 being suggested: — 



Cost of Eradication. Proportion of Bonus. 



Under £100 . . . . I21/2 per cent. 



£100 to £500 . . . . 25 per cent. 



£500 to £1,000 . . 33 per cent. 



£1,000 and upwards . . 50 per cent. 



It was further recommended that arsenite of 

 soda be sold at cost price; that the carrying of 

 Prickly-pear or jointed cactus from an infested 

 to a clean area be punishable with a heavy pen- 

 alty; that the planting of these two pests be 

 prohibited; that farmers whose lands were free 

 from pear be compelled to keep them clean ; and 

 that lands cleansed with Government assistance 

 be kept clean at the owner's cost. Moreover, all 

 public lands, whether belonging to the Crown, 

 to municipal bodies, or to railways, should be 

 brought under similar conditions. Further ex- 

 perimentation with mechanical and chemical 

 means was urged. 



The earlier methods of clearing Prickly-pear 

 were purely manual, the plants being chopped 

 down and then stacked. After a time the inner 

 portion of the mass would decompose, while the 

 new growth from the outer parts was broken off 

 and thrown on the heap. Ultimately the heap 



became dry enough to burn. The hardness of 

 the Karoo soil prevented the burial of the plants 

 (R.S.C., 1890, pp. 10-12; R.S.C., 1891, p. 4). 

 Cooper's sheep dip was tried as a means of de- 

 stroying Prickly-pear (Agr. Journ. Cape of Good 

 Hope, I., 1888, Nos. 9, 12, 14). 



About this time (Fischer, 1891 a, p. 443; 

 Macdonald, 1891 a, p. 24) it was proposed to 

 carry on experiments with scrub exterminator, 

 which had been found a success in India. This, 

 on analysis, was found to consist mainly of 

 arsenic and certain alkaline substances (Fischer, 

 1891 a, Appendix, p. 11; Juritz, 1892, p. 15). 

 The experimental work was initiated by A. 

 Fischer (1891 b, p. 133), who reported that 

 certain solutions of the Australian Scrub Ex- 

 terminator and also of arsenite of soda destroyed 

 the above-ground portion of the pear. The work 

 was carried on by A. C. Macdonald (1892 a, 

 pp. 21-3; 1892 e, pp. 112-3), who used, in addi- 

 tion, other sprays such as copper sulphate and 

 corrosive sublimate. The general result was 

 rather unfavourable, as new growth was pro- 

 duced by the semi-decayed plants, on account of 

 the failure of the chemicals to destroy the roots. 

 This result coincides with that obtained in 

 Southern India (Fawcett, in Fischer, 1892 a, 

 p. 24) . The cost of clearing per acre in the latter 

 country, when using the scrub exterminator, has 

 been worked out by Fischer (1891 a, Appendix, 

 p. iv.) to be over £84 per acre. 



Macdonald 's experiments were continued by 

 himself and Palmer (1892, pp. 276-7) and others 

 were carried out by Holmes and Davenport 

 (1893, p. 64).* As a result of the work of these 

 men it was found that the arsenical sprays are 

 not very effective against growing Prickly-pear, 

 but that if the latter be chopped down and 

 heaped, or if the bark be well pierced before 

 spraying, then destruction follows in a short 

 time, and the dead plants may be burnt. A con- 

 siderable saving in time and expense was found 

 to occur. The most effective strength of solu- 

 tion was shown to be obtained by dissolving 1 

 lb. of the arsenic compound in 8 or 9 gallons of 

 water. The poison was found to act more rapidly 

 if applied to the heaps after the plants had been 

 chopped down, winter time being the most suit- 

 able time for using it (Macdonald, 1894, p. 

 285). The Government, as a result of these ex- 

 periments, imported a supply of the arsenite of 

 soda and scrub exterminator and sold it to 

 farmers at 2i/2d. per lb., this being about half 

 cost price (Tooke, 1898, II., IV.; Macdonald, 

 1894, p. 285). 



Acting on the recommendation contained in 

 the report of the Parliamentary Select Commit- 

 tee (1898, p. v.), the Government, in 1898, dis- 

 tributed arsenite of soda free (R.S.C., 1906, p. 

 2; Nobbs, 1906, a, p. 9) ; but the supply was 



* Macdonald's work has been referred to by Mr. 

 Maiden (1898, pp. 984-7). 



