MEASUREMENT OF GROWING STOCK. 137 
MEASUREMENT OF GROWING STOCK. 
The Growing Stock of a Forest, or Volume of Stand- 
ing Timber, is equal to the sum of the volumes of all the 
trees. Where the tract is small caliper all the trees, or if the 
tract is large caliper all the trees on a small sample area selected 
as typical of the whole. If each species is in uniform stand, 
separation into species classes will be sufficient, but where much 
difference exists between individuals of the same species, due 
to conditions of growth, diameter and height classes in each 
species should be formed, and the volume of each class com- 
puted by itself. From the diameters obtained by calipering at 
breast height the average basal area is determined in each class, 
and trees of corresponding diameters in each class are felled and 
measured accurately. The volume of a sample tree, or the mean 
volume of several sample trees, times the number of trees, gives 
the volume of that class, and the sum of the volumes of the dil- 
ferent classes is the total volume of timber on the tract. The 
more sample trees that are measured the more accurate will be 
the results, as trees vary so much in shape that quite different 
volumes may be obtained for two trees of the same diameter and 
height. 
A Sample Acre of Jack Pine Shows the Following 
Stand: 
Diameter, Basal 
Breast Height. No. Trees. Area, 
BZ TMENE Si, asusainy arse aaa aR al 0218 
BVAMICM ES nuh cd Marmara tat nie ce aise ee NO 2946 
And chestns<cndae Joel Meenas. 30 5238 
CRI CHES yen at niaue Sins ta tana Choma ect ata 16 2.1824 
OraLiGheSgne canna Pe tigcyne cher oem oeetcie |G 6.4779 
7 MWUCKESc nse eivduacer wens steed RO ee Me ke 40 10.6920 
BUINCHESE oats wh enda Rul Meads santana aaa OO 20.9460 
OMAN GHESk igs cardia ccc d2 camo gece ueeananeseae SO 24.7408 
TO? UCM eS aces epee weiner Yew mead ha seen eum AO 25.0884 
fet) AMCHESH et ae ae eet waa A aN ee ey 29.1400 
Te tT CHES IS eoeik aesrnteas ere S reo tmnteaNaes 2 Seek moeane LL 8.6304 
13) ANCHCSuia eaten. eee aiemiisssTehoesaeeeen AO 8.2962 
THANCHES ic cnc s ake ae A eM eRe SAE Avena. <2 2.1380 
To IMCMESh tue Sock ats auts Qe 2 2.4544 
317 141.6357 
