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VOLUME OF WHOLE WOODS. 

 BEECH. 



SECTION II. DETERMINATION OF VOLUME BY MEANS OF 

 SAMPLE PLOTS. 



1. Definition. 



Instead of measuring all trees in a wood, a certain part of 

 the area may be selected, the volume on it ascertained, and 

 from it the volume of the whole wood calculated. Such a part 

 is called a sample plot. It may be denned as a portion of a 

 wood which contains an average volume of material per unit 

 of area. 



Having ascertained the volume of the sample plot, that of 

 the whole wood can be calculated in two ways : either according 

 to area, or according to the number of trees on the sample plot 

 and in the wood. 



Let 



A = area of wood, 

 a = area of sample plot, 

 V volume of wood, 

 v = volume of sample plot, 



