1 66 Forestry Quarterly 



MENSURATION, FINANCE, AND MANAGEMENT. 



One of the propositions to reduce the 

 Cross Section amount of measuring in determining con- 



Area by tents of stands has been that of Konig by 



Space Number the use of the ' ' space number ' ' . 



The space number is the relation between 

 distance and diameter, i.e., the average distance at which the 

 trees stand apart, divided by their average diameter. The total 

 area of a stand may be conceived as divided into as many 

 squares as there are trees, each square being the standing room 

 of the tree, the average of the sides of the squares being the 



average distance, and a = is the distance number. We have 



d 



Trd' 

 then the proportion A (area) : c (cross section area) = s'' : — .' 



4 



hence c = A 



d' IT _ A IT _ .7854^^ 



s i\ a t\ a' 



The difficulty lies in determining .y with sufficient accuracy. 

 Schleicher investigates the methods proposed by various 

 authors, shows them faulty and liable to grave errors. He pro- 

 poses a new method which apparently furnishes tolerably accu- 

 rate results (at most not over 7% error) and requires only one- 

 third the time of calipering the whole stand. 



It consists in making the measurements in groups of 6 or 8 

 trees at regular distances apart, say 50 to 100 steps, without se- 

 lecting ; the distance of a center stem from the others (outer 

 stems) being measured and all being calipered and recorded by 

 diameter classes. As can be shown, if the number of outer 

 stems is n and the average distance of the latter from the center 



stems e, then s = e . For groups of 6, 7,8 



1,4142^ — 16568 



trees (= «), respectively the factor becomes .8786, .8492, .8284. 

 The rest of the calculation is self-evident. 



Die Ermittelung der Bcstandis-Stamnigrundfldche init Hiilfe der Ab- 

 standszahl. Allgemeine Forst- und Jagdzeitunj^, Feb. 1906, p. 37-45. 



To show that the principles of the soil 



Forest Valuation rent can be and are practically applied. 



in Dr. Wimmenauer publishes with full de- 



Practice tails on 23 quarto pages such a valuation 



of rather complicated conditions used in a subdivision of proper- 



