NIGERIA 181 
it is somewhat high, and this very considerably increases the cost of 
the final establishment of the plantation. For some years the cost in 
many cases amounted to £10 per acre for the first year and £1 or £2 
for subsequent years, for the cost of ‘‘ beating up’ and keeping the 
plantations clean. With the greater experience gained both in regard 
to the habits of the different trees and in the methods of reproduction 
most suitable to various parts of Nigeria, the cost has been somewhat 
lessened. However, even so, the cost compared to European or English 
plantations is not abnormally high. In Africa there is no land to buy, 
and no wire-netting is needed for the plantations, and the land usually 
planted has not a “ letting ” or “‘ sporting ”’ value, as it has in England. 
The buying out or compensating of the native rights of the usufruct 
of the soil is not so very expensive, especially when it is spread over 
comparatively large areas, as it usually is in West Africa. Then, again, 
even with the cost of £10 per acre, the total value of a crop after fifty 
or sixty years would certainly not be less than 3s. per cubic foot of the 
timber, which thus allows ample margin for 5 per cent. compound 
interest on the original outlay, and a profit besides. In many cases 
the timber would be worth a great deal more, and also the value of 
the intermediate thinnings is not inconsiderable. Both these factors 
have been left out of the account, in order not to in any way exaggerate 
or make too optimistic estimates of the value of a forest plantation. 
But beyond the financial side of the value of forest plantations, 
more especially in a tropical country like Nigeria, is the very valuable 
indirect effect they have on the whole welfare of the country. 
First of all, plantations in forest groves improve and beautify a 
locality, whether on the level or amongst hills. 
In the second place, the forest induces a greater rainfall in itself 
and its immediate vicinity. 
Then the rainfall which actually falls in the forest is partly re- 
evaporated to fall again, thus making extra rainfall, and also the rain 
which actually reaches the ground in the forest is only gradually 
absorbed, thus making the flow of springs and rivers regular. 
Both on the level and especially on slopes, a covering of trees, 
such as a forest, hinders the washing away of the surface soil or tilth 
of the land. 
Forest trees only require one-twelth of the mineral matter out 
of the soil that an agricultural crop does, covering the same 
area. 
In a forest plantation there is always greater humidity in the air, 
and thus many plants of economic value, such as cocoa, can grow in 
its vicinity, which would otherwise not be possible to be grown in 
that locality. 
A forest acts as a moderating influence on the temperature of 
the air, being lower inside the forest than outside, when the sun is very 
