FORESTRY 1 79 



logy and plant physiology, particularly in relation to the tran- 

 spiration stream of growing trees, and the amount of moisture 

 added to the atmosphere by a forest area of a given type. Until 

 such data are available, it appears essential to preserve areas of 

 forest land at least sufficient to ensure the continuation of present 

 water-supplies and to avoid soil erosion. This necessity is usually 

 met by the establishment of areas of reserved forest (which need 

 not, of course, be closed to commercial exploitation) on high 

 ground, especially in the neighbourhood of watersheds. The 

 principal object is to ensure that the streams and rivers are main- 

 tained as perennial and not reduced to mere intermittent floods, 

 as would be the case if forest growth were removed and the soil 

 eroded. 



In many parts of Africa, especially where native agriculture is 

 based on shifting cultivation, the destruction of forests has gone 

 beyond the safety limit. It has been difficult to enlist the support 

 of native administrations in the creation of forest reserves, owing to 

 their failure to appreciate the necessity of measures which may 

 involve a diminution in immediate revenue. 



Another matter in which it appears that stricter control is 

 desirable is in the grant of concessions to mining companies to cut 

 forests for timber and fuel. There are conspicuous examples in the 

 Gold Coast where such concessions, granted forty or fifty years 

 ago, have led to large-scale destruction of evergreen forest around 

 mining areas, and there appears to be no organization for replant- 

 ing. With the rapid development of mining in other parts of 

 Africa, especially in Northern Rhodesia, Tanganyika and Kenya, 

 there is danger that this situation may be repeated on a large 

 scale. Since a supply of timber is essential for mining operations, 

 it would seem that provision for the replacement of forest destroyed 

 is desirable. 



ORGANIZATION 

 BRITISH 



The central institutions in Great Britain which deserve mention 

 are as follows: 



The Imperial Forestry Institute at Oxford, now under the direction 

 of Mr. J. N. Oliphant, is the Empire centre for advanced training 



