562 Forestry Quarterly 



For pine and for beech approximately the same relation has 

 been established. 



If the stem classes have been arranged with equal cross-section 

 areas, the stem class averages will be for spruce — 

 I II III IV V 



75 94 106 122 138 per cent 

 of the stand average tree's cross-section. 



These percentage calculations are especially convenient when 

 the calipering has been done with a registering caliper (Wim- 

 menauer). 



Some applications of the increment per cents in determining 

 felling budgets are given. 



The process of determining a stand increment is given as fol- 

 lows : Calipering the stand (or a sample area or strip) ; all trees 

 which during the period for which the increment is to be figured 

 are likely to be felled in thinnings are recorded separately from 

 the main stand. The latter is divided in five diameter classes of 

 equal numbers or equal cross-section areas, and the diameter of 

 the average class trees is calculated. Then three to four speci- 

 mens of each average diameter of proper height and form are 

 found, and with the use of the increment borer (being careful 

 to measure higher than breast high if root swellings make it 

 desirable) the diameter increment is measured, measuring also 

 the height. The borings should be made at two opposite ends of 

 the diameter, but if four samples are taken this is hardly neces- 

 sary. The bored core is placed in an envelope properly marked 

 for identification, and all the investigation and calculation is done 

 in the house. 



Zuwachsermittlung am Baum tind am B^stand. Forstwissenschaftliches 

 Centralblatt, June, July, 1911, pp. 293-315, 319-370. 



UTILIZATION, AIARKET AND TECHNOLOGY 



In addition to the potash from hedge 

 Wood-waste clippings and vegetable refuse, etc., the 

 as Source of writer draws attention to the value of wood 

 Potash scraps, sawdust and shavings, produced in 



enormous quantities in sawmills. In lo- 

 calities where this wood-waste is not salable for other purposes, 

 it may with advantage be converted into ash and used as a potash 



