much of the continent — against the ravages of erosion and desiccation. I 

 have since, on several occasions, reiterated the same thought. In the ab- 

 sence of measures providing for the conservation of country hitherto under 

 'fly*, overstocking would readily produce a far worse curse than the 'fly': 

 additional foci of desiccation. It is heartening to read that recently the 

 tribesmen in Sukumaland, Lake Province, have accepted a plan for the re- 

 duction of their stock by culling. If successful and if applied generally 

 this may have far-reaching influences on wise use of land freed of 'fly'. 



Again I make a plea for the planned freeing of all such country from the 

 'fly* and its appropriate use and conservation on an organized basis. 



(ii) Solution of the problems of economic and acceptable livestock reduction 

 and of the management of natural pastures in the drier portions under re- 

 view, is made all the more urgent because of the marked influence of 

 selective grazing and browsing and the witholding of fire upon the rapid 

 establishment of vast areas of thorny and other thicket and scrub, in which 

 Acacia and Dichrostachys frequently play a role. Nfillions of acres in South, 

 Central and East Africa are either in or advancing toward this condition — 

 its sole merit being that its impenetrability renders the ground it covers 

 safe from further trampling by livestock. 



Measures for the rehabilitation of such areas, by means of scrub and thic- 

 ket thinning and removal accompanied by protection for a time and, later, 

 by systematic management of grazing, must be introduced if vast acreages 

 are not to be permanently lost to the use of man — otherwise a desert due 

 to erosion would be replaced by one of thorns! 



(iii) Large-scale enterprises aiming at the ranching of the arid and semi- arid 

 regions, where such are Tsetse- free, will succeed to the degree to which 

 those responsible undertake rational preliminary survey of the potentiali- 

 ties, the provision of adequately distributed water points, the management 

 of the natural grazing and browse, the setting aside of reserve grazing or 

 fodder against hazard of drought and the consistent giving of attention to 

 pests and diseases. 



Considerable potential there is in the Kalahari and in parts of Rhodesia 

 and Tanganyika for enterprises of the right kind properly planned and direc- 

 ted. Hasty, ill - directed action would end in disaster. 



(iv) In the sub - arid regions — notably in Rhodesia and Tanganyika, large-scale 

 mechanized crop production should not be attempted, no matter how encoura- 

 ging the temporary successes on the now small - scaled scheme at Kongwa 

 or elsewhere in similar country may appear. The costs of clearing of vege- 

 tation, the preparation of the land and of periodic losses due to serious 

 droughts would not be justified. Nevertheless, it remains true. that on lower 

 lying, alluvial soil within the sub- arid areas small scale mechanized pro- 

 duction of Groundnuts and Sorghum may be economically worth while. In 

 such areas Maize should normally be considered uncertain, owing to the 

 marginal nature of the regions in terms of rainfall reliability. 



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