206 Forestry Quarterly. 



decreasing uniformly with increasing height while spruce shows 

 24 to 12%. 



Kiibikinnchollet och form en hastallen och grancn. Skogsvords foren- 

 ingens Tidskrift. December, 1908. 



A "friend of the selection forest," Ober- 

 Increment forster Christen, points out that careful in- 



in vestigations of the current increment in 



Selection typical selection forest would show that it 



Forest. exceeds that of even-aged forest on similar 



sites. Only the difficulties of ascertaining 

 with precision the increment under the constantly changing con- 

 ditions of the selection forest are in the way of establishing this 

 fact. 



In the French methode du controle, which consists in deter- 

 mining the current increment by measurements at two different 

 periods of time, (I = V — V + N), the increment on N, which 

 is the budget cut between the two periods of time, is neglected, 

 which may make a very considerable difference. The author does 

 not overlook that portions of the increment occurring due to the 

 influence of light on remaining trees may be offset by the damage 

 done to the young growth by fellings. He finally develops a 

 very complicated formula which is to take care of all the varied 

 influences, and connect the usual discrepancies of calculation. 



Measurements in four different localities 3,000 to 4,000 feet 

 above sea level, carried out with this care brought out increments 

 of 114, 133, 137, and 173 cubic feet per acre. In even-aged 

 spruce stands in Switzerland in the hill country up to 2,500 feet 

 bring in 80 years an average increment of 274 for best and 133 for 

 poorest sites which on higher altitudes is reduced to 266 and 114 

 respectively, including brushwood, while in the computations for 

 the selection forest these were neglected. 



Zur Brmittlung des laufenden Zuwachses speziell im Plenterwalde. 

 Schweizerische Zeitschrift fur Forstwesen, February-March, 1909, pp. 

 37-41, 82-87. 



The carefully collected normal yield tables 

 Practical of the German Experiment Stations were, 



Yield according to Ostwald, to serve two objects : 



Tables. first, to give an insight into the laws of 



growth, which they have done satisfac- 

 torily ; secondly, to furnish practical aids in estimating for pur- 

 poses of working plans. 



