44 



BULLETIN 544, U. S. DEPARTMENT OF AGRICULTURE. 



Table 18. — Norway spruce 1 (1'ir, a e < celsa). Xormal yield table for northern and central 



Germany. 







QUALITY 



I. 







Age. 



Number 



of trees 

 per acre. 



Basal 

 area.'- 



Average 



height. 



Diameter 



of 



average 



tree. 2 



Yield 



per 



acre. 3 



Forest 

 form 

 factor. 



Years. 



40 



50 

 60 

 70 

 80 

 90 

 100 



1, 254 

 799 

 557 

 421 

 340 

 284 

 247 



8q. ft. 

 194.8 

 216. 1 

 231.5 

 241.8 

 250.7 

 259.2 

 266. 7 



Feet. 

 47.9 

 61.4 

 72.4 

 SI. 3 

 88.6 

 94.8 



100.0 



Inches. 

 5.4 

 7.2 

 8.9 

 10.4 

 11.8 

 13.2 

 14.4 



Cu. ft. 

 4,973 

 7,067 

 8,798 

 10, 227 

 11,425 

 12, 457 

 13, 367 



0.531 



. 533 

 .525 

 .520 

 ..",] 4 

 .507 

 .501 







QUALITY II. 







40 



1,924 



140.8 



30.2 



3.7 



2,115 



0.495 



50 



1,216 



162. 4 



42.0 



4.9 



3,673 



. 534 



60 



840 



178.9 



52.2 



6.2 



5,059 



.539 



70 



628 



1S9.2 



61.0 



7.4 



6,274 



.539 



80 



500 



200.0 



67.9 



8.5 



7,317 



..534 



90 



424 



209.5 



73.5 



9.5 



8,217 



.528 



100 



380 



217.7 



78.4 



10.2 



8,960 



.522 



QUALITY III. 



40 



3,587 



95.5 



17.6 



2.3 



638 



0.380 



50 



1,969 



116. 3 



25.3 



3.3 



1,410 



.479 



00 



1,270 



131.3 



33.3 



4.5 



2,403 



.550 



70 



928 



142.5 



41.1 



5.4 



3,344 



.571 



80 



750 



152. 2 



47.2 



6.2 



4,161 



.579 



90 



651 



160. 6 



51.8 



6.8 



4,823 



.580 



100 



597 



167.3 



55.4 



7.3 



5,352 



.577 



1 From '-"Waehstum und Ertrag normaler Fichtenbestande, " by Adam Schwappach, Berlin, 1890, as 

 translated by H. S. Graves (pp. 417 and 41S, Forest .Mensuration, New York, 1906), revised on the basis of 

 3 instead of 5 quality classes. 



2 At 1.3 meters (4.27 feet) from the ground. 



a Derbholz (top diameter of 2.76 inches outside the bark). 



A comparison ' of the values in Table 17 for red spruce with those 

 of Table 18 for Norway spruce brings out the importance of good 

 management in the development of stands. One of the first things 

 to arrest the attention is the marked discrepancy between red spruce 

 and Norway spruce in height and volume growth in Quality I. 

 Even red spruce's advantage in having only its best growing trees 

 included is insufficient to overbalance the deficiency in height. One's 

 first impulse is to take this as confirming the widely accepted opinion 

 that the growth qualities of red spruce are markedly inferior to those 

 of Norway. Yet if that were so, the discrepancy would prevail 

 throughout the three quality classes, which it does not do. It is 

 considerably less marked in Quality II and disappears almost alto- 

 gether in Quality III. To explain this difference, one must take 

 into consideration the intensity of management of Norway spruce in 

 the different quality classes. Thus, in Quality III, where Norway 

 spruce was l<;'-f intensively managed, thinnings began late, between 



1 In making the comparison it should he continually borne in mind (1) that the red spruce table is based 

 on the measurement only of dominant and intermediate trees in 59 volunteer stands, whereas the other 

 includes all <:«•<•. i : rees i" ><K) managed tands, four-fifths of which were artificially regenerated, and (2) that 

 the utilization is not so close for red spi Qi e as for Norway either in the top or at the stump. 



