266 COLLECTION OF STATISTICS. 



or sowing, the manner in which the wood has been tended, 

 cleanings, thinnings, pruning, natural phenomena which have 

 affected the development, etc. Such a history is very useful 

 in judging the results of the past method of treatment, and in 

 determining the future treatment. 



/. Volume. 



All methods of determining the yield in material require a 

 measurement of the volume, but to a different extent. For 

 some it is necessary to measure all woods, excepting only those 

 which are very young, and which are estimated, either direct, 

 or with the assistance of yield tables. For other methods 

 only those woods require to be measured, which will come 

 under the axe during the immediate future of, say, 10 to 20 

 years. 



Where a fine financial management is followed, all woods 

 which are close to ripeness, or of which the ripeness is 

 doubtful, must be accurately measured, so as to calculate the 

 per cent, with which the capital is working. 



For the determination of the capital value an accurate 

 measurement of the volume is indispensable. 



The volume should be given separately for the different 

 species, if their value per unit of measurement differs con- 

 siderably. It is useful to give all volumes in solid measure, as 

 solid cubic feet. The proportion between the different classes 

 of produce need only be given for each working section ; best r 

 according to local proportionate figures, if such are available. 



The different methods, according to which the volume can 

 be measured, have been described at pages 43 to 71. The 

 choice of the method of measurement depends on the circum- 

 stances of each case. 



g. Increment, Capital Value, and Forest Per cent. 



These matters have already been dealt with in full detail. 

 The determination of the quantity increment is required for 

 the calculation of the yield. It must be done for all woods, 



