106 SECTIONAL ADDRESSES 
hand, has lost much of its fertility through leaching, and possibly has 
become partly lateritic. It seems to be covered by somewhat xerophytic 
bush wood. The very porous soils developed upon the thick Kalahari 
sands of Barotseland would seem to be fairly good so long as the tree 
cover is maintained, with roots reaching the ground water, but to suffer 
rapid degradation when this is cut down. 
DEPREDATIONS BY MAN. 
The inquiry has elicited certain facts about the modification of the 
natural vegetation by the natives. The great majority of the people live 
upon their crops, and most of these are raised in partial clearings of the 
savanna. ‘The natives are truly men of the trees, apart from which they 
cannot live. The essential feature of their system of shifting agriculture, 
a system well known throughout the forests and savanna of inter-tropical 
lands, is the annual felling or pollarding of trees and the application to the 
soil of the ash derived from burning the wood on the site of their gardens. 
The name given to the practice in north-eastern Rhodesia is chitemene or 
vitemene, meaning ‘ those which have been cut.’ The area of woodland 
cut for a garden of given size of course depends first upon the luxuriance 
of the trees, and secondly upon the nature of the practice—whether 
pollarding or felling. Throughout the.drainage basins of the Kafue and 
upper Zambezi, as well as east of the Luangwa, it seems to be the habit 
to fell trees and to burn all branches, leaving the trunks to rot. This is 
also the method in part of Fort Rosebery and among the Awisa of Mpika. 
But to the north of the latter Districts trees are usually only pollarded, 
and this also seems to be the case in two central Districts, Mkushi and 
Serenje. The estimates of the ratio of timber area cut to area of garden 
vary between 4:1 and 10:1. The estimates of the period required for 
recovery of the woods are more numerous, but they are difficult to inter- 
pret in view of the inadequate accounts of the vegetation. In Mpika 
District the pollarded woods of the Awemba are left for about seven years, 
we are told, while the felled timber of the Awisa would require a genera- 
tion to recover. Yet several District reports mention rest periods as 
short as four or five years ; in others these are between ten and twenty, 
and in Barotse thirty to thirty-five years. 
The degree in which the savanna has degenerated under this system of 
agriculture depends largely upon the density of the population. Many 
writers point out that tracts of the natural vegetation still exist simply 
because the population is small—as, for instance, in Chinsali with three per 
square mile. But such figures are misleading, for the actual densities on 
land desirable from soil and water qualities are very much greater. More- 
over, the native cuts wood for many purposes besides that of manuring 
his garden. He needs timber for a new hut every few years, for heavy 
garden fences, and for canoes. He fells trees to obtain honey, he strips 
trees of their bark. ‘ Bark,’ writes the author of the report on Mongu,!° 
“comes more frequently into daily life than anything else ; every piece of 
rope used by natives and most of that used by Europeans is made of it, 
10 J. F. Warrington. 
