

62 PRACTICAL FOREST MANAGEMENT. 



the use of volume tables is evident. As sufficient data are collect- 

 ed existing volume tables will be revised and new ones prepared 

 for all the principal species in the United Provinces to show 



(a) total volume of wood (timber plus fuel) down to 2 inches 

 diameter, 



(6) total volume of timber in the round down to 8 inches 

 diameter, 



(c) volume of converted or sawn timber. 



But in estimating sawn timber outturn, an additional factor 

 (which may be called the reducing factor) comes into consider- 

 ation. As defined, sawn timber figures are based on best conditions 

 of conversion and absence of rot, etc., i.e., they represent the 

 optimum figures of practical exploitation that may be expected in 

 the United Provinces forests. For many felling coupes a reducing 

 factor must be applied to allow for 



(1) a certain amount of rot and hollowness, 



(2) less intensive conversion. 



This reducing factor can only be obtained by experience for 

 each locality, forest or coupe separately, but when once obtained, 

 a standard set of volume figures will prove very useful for obtaining 

 -accurate results. 



