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One definite calculation of the rate of growth of tropical forests 

 in a part of the world with climatic conditions approximating to those 

 of our Evergreen Forest has been published by Mr. I. H. Burkill, 

 Director of the Botanic Gardens, Straits Settlements, in " The Gardens 

 Bulletin," Vol. II., page 145. An opportunity was taken of studying 

 a piece of jungle of a known age, and the conclusions arrived at by 

 Mr. Burkill are that it takes at least 100 years from the upspringing 

 of the first growth of secondary jungle on a cleared area before the 

 giant forest trees are established as they are found in the virgin forest. 

 The piece of jungle examined, which was 30 years old, gave the follow- 

 ing number of plants : — 



378 trees of 18 feet or more. 

 2,728 woody plants of 2 to 18 feet. 

 27,342 smaller plants, mostly small, woody seedUngs. 



30,448 in all, or 96,660 plants to the acre. 



Assuming these figures, which are the only ones which provide 

 any kind of basis for calculations, the annual increment per acre 

 must be regarded as approximating to 50 cubic feet in the forest 

 (Guinea Zone) area. In Table I. it will be seen that only an area of 

 11,400 square miles can be considered as available for timber and 

 minor forest products. With regard to column 6, Table II, " Loss; 

 Waste, Decay, etc.," as the crop is very mixed, it is little subject to 

 the ravages of entomological and mycological pests, and the area under 

 consideration, i.e., the Guinea Zone, is not at present affected by the 

 fire factor. Under these circumstances it appears that an estimate 

 of 5 per cent, of the total increment may be allowed for loss. 



The above statements appear as follows when put into tabular 

 form : — 



TABLE II. 



Annual Increment within the Guinea Zone in Cubic Feet. 



*Although there are various areas in Ashanti which have been declared " Forest 

 Reserves," the Department has not yet had sufficient stafi to attend to them and, 

 consequently, no distinction has been made by the natives between them and other 

 forests. There is, therefore, no forest actually under State Control. 



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