204 FELLING AND CONVERSION OF TIMBER. 



feet without fractions. Squared balks of valuable wood like 

 mahogany are, however, sold by the superficial foot. Tr.J 



Whether timber should be measured with or without bark 

 depends on local custom. In the case of winter-fellings, the 

 bark is included, and wherever summer-felled or other peeled 

 wood is measured, 12 to 15 per cent, is added to the cubic con- 

 tents to allow for the absent bark. This is done because the 

 yield of the forests in the working-plan is estimated with the 

 bark on the trees, but the German timber-trade is most 

 anxious that bark should not be included, and this method 

 Gayer strongly recommends for adoption everywhere in the 

 interests of uniformity. 



A universal system of measuring timber without bark pre- 

 supposes that the bark of logs is removed at the measuring 

 point, and that no addition is made for peeled wood. In the 

 case of coniferous logs, the difference in diameter between 

 barked and unbarked trees is f inch on the average, some- 

 what more in the case of pines, and for logs under 10 inches 

 in diameter, less than J inch. 



In the case of roughly barked broadleaved trees, such as oak 

 and ash, the bark is 12 to 15 per cent, of the total volume ; 

 in the elm, up to 18 per cent, and more; the birch 11 per 

 cent.; the Scotch pine, 11 to 15 per cent.; spruce logs and 

 blocks, 12 to 13 per cent. ; silver-fir ditto, 17 per cent, and 

 more. It should be noted that on good soil with a dense 

 growth, the bark is least, whilst in unfavourable localities and 

 open woods it is at a maximum. 



Whenever stems are sold at their full length, the measure- 

 ment for timber stops naturally where the small end becomes 

 less than the minimum in timber-classes, and the rest of the 

 log can be measured only as firewood. 



l<> Dimensions. 



In some localities, where there is an extensive trade in logs, 

 it has been for a long time customary to arrange them in 

 classes which do not depend on their cubic contents. Thus, 

 for ea,ch class (1 lolliiiulcrlioh, etc., of the Black Forest), a log 

 of average dimensions is assumed as a standard and by its 



