SOME FOREST SECRETS 



ing which shows they may increase at least the amount 

 of precipitation over their own immediate neighbour- 

 hood. 



Woodlands are often of the greatest value in exposed 

 locations as affording shelter and protection from storms 

 to agricultural crops and plantations. 



Generally trees improve soil; an unproductive area 

 of land which is incapable of bearing an agricultural 

 crop may sometimes be made fertile by planting trees. 



The value of the forests in assisting agriculture, can 

 never be overrated; the one is the complement of the 

 other. 



It is often found that in virgin forests there is no in- 

 crease, the annual growth being about balanced by the 

 annual decay. 



In dealing with this subject in my research, I was at 

 first greatly handicapped because so little information 

 about annual wood increment of the trees was available 

 and I was forced to rely largely upon data obtained in 

 other countries where the forests have been under close 

 observation for many years. 



In South Africa and elsewhere it has been proved by 

 long experience that more timber is grown per acre and 

 that growth is much more rapid, on land where some 

 attention is given to systematic forestry than on that 

 which is left to itself. This would only appear to be rea- 

 sonable when we consider that much of the energy of 

 trees may be expended in fierce competition with neigh- 

 bours which may weaken them all and perhaps bring 



241 



