m 



dry areas, was practically wiped out in South 

 Africa by a fungus parasite— a kind of Rust; 

 and if an organism similar to this was to be found 

 m association with Prickly-p*ar, there was 

 something to be expected from the discovery in 

 accomplishing what was desired. 



In several places Prickly-pear plants were 

 remarked showing lack of vigour and evidence 

 of general constitutional derangement — e.g., 

 various degrees of etiolation, areas of skin dis- 

 coloration, &c. This phenomenon suggested 

 soil imperfection of one kind or another as a 

 probable cause. In official reports (unpublished) 

 to the Department of Agriculture of Queensland, 

 relating to the occurrence of alleged Opuntia 

 diseases at Nundah and "Westwood respectively, 

 one of the Commission has pointed out the in- 

 fluence of this factor in occasioning ill-health in 

 the class of plants under consideration (Tryon, 

 1908, 1911, p. 9). Further, in South Africa 

 it has been found that there is a distinct con- 

 nection between a comparatively high lime con- 

 tent in the soil and the presence of at least one 

 kind of Opuntia — i.e., the pest pear, 0. decumana. 

 Dr. G. F. Juritz, the Agricultural Chemist to the 

 Union Department of Agriculture, and whose 

 work on the soils of South Africa gives weight to 

 any statement from him regarding South African 

 soil composition, informed the Conunission that 

 most of the land on which the plant was trouble- 

 some possessed a high lime content, instancing 

 the eastern part of the Karoo — e.g., Cradock and 

 Somerset Bast, outside which area, i.e., " in dis- 

 tricts deficient in lime," it was grown only 

 as a hedge plant or for its fruit, and, although 

 0. decumana was also said to be plentiful along 

 the eastern coastal belt where the soils did not 

 contain much lime, other factors there might be 

 concerned in determining its prevalence. With this 

 exception, generally speaking, " where the land 

 was poor in lime pear did not become a pest." 

 The influence of this particular character of the 

 soil on the occurrence of Prickly-pear might be 

 taken into consideration in any forecast of the 

 direction of its future extension, as well as 

 explain defects in its growth such as are alluded 

 to. 



DESTRUCTION BY UTILISATION. 



The only naturalised species which has been 

 utilised to any extent is 0. decumana, the Kaal- 

 blad variety having been made more use of than 

 the thorny form or Doornblad. As already men- 

 tioned, certain other varieties — " anacantha " 

 and " manado," as well as a distinct species, 

 Nopalea cochinelifera — have been grown as an 

 accessory fodder crop for ostriches and stock, 

 while 0. monacanfha is used occasionally as a 

 hedge plant either alone or in company with 

 the Doornblad. The succeeding remarks regard- 

 ing utilisation refer to 0. decumana, and as they 

 have reference to a plant related to one of the 

 Queensland Prickly-pears their inclusion appears 

 justified. 



Utilisation as Foddee for Stock. 

 There is a considerable amount of literature 

 published in South Africa (mainly Cape Colony) 

 on this subject, and much evidence has been col- 

 lected by the Commission; but it can be sum- 

 marised in a short space. 



Owing to the fewness or absence of spines on 

 the joints of the Kaalblad, this variety has l^een 

 used much more extensively than the more thorny 

 form, though it appears from experiments carried 

 out by Mr. Thornton, Principal of the Grootfon- 

 tein Agricultural College, Middelburg, Cape 

 Province, as well as from the experience of many 

 farmers (R.S.C., 1898, p. 21; Adams, 1895, p. 

 447), that the Doornblad segments are sweeter 

 and more nourishing, but the labour involved in 

 removing the spines by singeing or otherwise is 

 a serious consideration. Hence it is the Kaalblad 

 which IS used; while the Doornblad remains and 

 fruits, and has become the dominant form. 

 The pest pear, of South Africa is thus the Doorn- 

 blad variety of 0. decumana, the form which 

 had been determined as 0. triacantha by the 

 authorities at Kew. The singeing is usually 

 done over a kind of gridiron, and is rather over- 

 done than underdone. 



Prickly-pear has been used to a considerable 

 extent as fodder, more especially during times 

 of scarcity. As a rule, some other material is 

 added to it (Macdonald, 1891 b, p. 29). From 

 evidence obtained in various parts of South 

 Africa, it appears that stock, ostriches, cattle, 

 pigs, &c., can be maintained on a ration of pear, 

 and can actually thrive on it if the ration be 

 supplemented by "mealies" (maize), hay, 

 lucerne, grain, linseed meal, &c. If sufSeient 

 fruit of the plant be added, then stock may be 

 actually fattened on a Prickly-pear diet. 



In some places farmers, having removed the 

 pear, have replanted in a feneed-olf area so that 

 it might be available as a stand-by in seasons of 

 drought. In a few cases, such as on certain 

 Prickly-pear farms in the Cookhouse and Graaff 

 Reinet districts, no supplementary fodder had 

 been used, and the cattle and pigs from these 

 farms survived right through drought conditions 

 and maintained their condition. It is well known 

 that some animals become confirmed pear-eaters. 

 Besides this, there is a large amount of Kaal- 

 blad in these localities, hence the injuries which 

 commonly follow as a result of feeding on 

 Prickly-pear are not serious. The Commission 

 saw considerable areas of dense pear land at 

 Cookhouse, where the cattle were browsing on the 

 Kaalblad and keeping it quite short, while the 

 Doornblad remained untouched. 



It is admitted that pear will keep stock 

 alive, and this has been made a reason against 

 the elimination of the Kaalblad. On the other 

 hand, it is pointed out that the mere occupation 

 of the land by the pear prevents the growth of 

 other plants which might be utilised for the 

 same purpose during drought conditions, with 

 less danger. 



Many farmers have retained a clump of pear 

 on their farms, but have securely fenced it, so 

 that live stock cannot distribute the seeds or 

 joints and thus be the means of scattering the 

 pest still further. This clump of reserve fodder 

 is thus regarded as a form of insurance against 

 the evils following drought. 



Prickly-p:ar is fed quite commonly under 

 certain conditions to cattle and ostriches, also 

 to pigs and goats, and occasionally to horses. 



