GROWTH PER CENT IN QUALITY AND VALUE 435 



334. Growth Per Cent in Quality and Value. Growth in money 

 value of a stand is' treated in Forest Valuation. 1 This depends upon 

 the three factors mentioned in § 244, namely, increase in volume, in 

 quality, and in unit price independent of the other two factors. The 

 growth in quality differs from that in volume, since it tends in a measure 

 to raise the value of the previous growth, especially when this increased 

 quality is due to increased dimensions. Per cent increase in value is 

 usually computed as an annual per cent found by dividing the periodic 

 per cent by the years in the period, and is applied to the volume at 

 the beginning of the period, thus showing simple interest on the initial 

 value. When thus expressed, the per cent of increase is made up of 

 the sum of the per cents due to each of the three separate factors. 

 For young and immature timber, growth per cent in volume forms the 

 chief element of increase, but as the trees reach maturity this diminishes, 

 and is greatly exceeded by per cent increase in price due to quality, and 

 to unit prices — so that the per cent of increment in value may con- 

 tinue for a much longer time than that of volume. 



The growth in quality of a stand can be measured by the use of 

 graded log tables (§74) or graded volume tables (§165) provided it 

 is carefully ascertained that these tables apply to the trees in the stands 

 to be measured, at the successive ages. 



References 



A Practical Application of Pressler's Formula, A. B. Recknagel, Forestry Quarterly, 



Vol. XIV, 1916, p. 260. 

 Table for Determining Financial Increment Per Cent for Trees Based on their 



Market Values, Erling Overland, Translated by Nils B. Eckbo, Forestry Quar- 

 terly, Vol. V, 1907, p. 36. 

 Increment Per Cent, Schiffel, Centralblatt f. g. d. Forstwesen, Jan., 1910, p. 6. 



Review, Forestry Quarterly, Vol. VIII, 1910, p. 377. 

 Hilfstafel zur Zuwachserhebung, Forstwissenschaftliches Centralblatt, Apr., 1911, 



p. 200. Review, Forestry Quarterly, Vol. IX, 1911, p. 321. 

 Relative Increment of Tree Classes, Review, Forestry Quarterly, Vol. IX, 1911, p. 



633. 

 Zuwachsuntersuchungen an Tannen, AUgemeine Forst- und Jagdzeitung, Sept. 



1907, p. 305. Review, Forestry Quarterly, Vol. V, 1907, p. 431. 

 Ueber Zuwachsprocent, Centralblatt f. d. g. Forstwesen, Jan., 1910, p. 6. Review, 



Forestry Quarterly, Vol. VIII, 1910, p. 377. 



1 Forest Valuation, H. H. Chapman. John Wiley & Sons, N. Y., 1915. 



