LIFE HISTORY OF LODGEPOLE PINE IN EOCKY MOUNTAINS. 31 

 DENSELY STOCKED STANDS. 



Table 8 shows the yield of stands which are densely stocked, but 

 jnot so crowded as to cause stagnation of growth. The figures were 

 obtained on the Deerlodge National Forest on the best quality of 

 site. Most of the sample areas measured were 1 acre each. 



Table 8. — Average yield per acre of densely stocked stands of lodgepole pine at 

 different ages on the oest sites {Quality I), Deerlodge National Forest, 

 Mont. 



Age in 



years. 



Basal 



area, 



square 



feet. 



Trees per acre. 



Aver- 

 age 



diame- 

 ter, 



main 



stand. 



Aver- 

 age 

 height, 

 main 

 stand. 



Yield. 



Annual growth. 



Entire 

 stand. 1 



Main 

 stand. 2 



Mean. 



Peri- 

 odic. 



Mean. 



Peri- 

 odic. 



40 



No. 

 106 

 128 

 144 

 156 

 166 

 174 

 180 

 184 

 188 

 192 

 194 

 196 

 198 



No. 



1,550 



1,250 



1,000 



825 



725 



650 



600 



535 



500 



460 



430 



415 



400 



No. 

 50 

 175 

 225 

 255 

 280 

 300 

 320 

 330 

 345 

 350 

 355 

 360 

 370 



Inches. 



7.0 



7.5 



7.7 



8.1 



8.5 



8.8 



9.0 



9.4 



9.6 



10.0 



10.3 



10.5 



10.6 



Feet. 

 36 

 46 

 56 

 60 

 64 

 66 

 68 

 70 

 72 

 74 

 75 

 76 

 77 



Cu.ft. 

 1,400 

 2,250 

 3,100 

 3,800 

 4,350 

 4,900 

 5,400 

 5,800 

 6,200 

 6,550 

 6,850 

 7,150 

 7,400 



Bd.ft .3 



4,800 

 6,200 

 7,500 

 9,000 

 10, 800 

 12,600 

 14, 800 

 17, 200 

 19, 800 

 22, 200 

 25, 000 



Cu.ft. 

 35 

 45 

 52 

 54.3 

 54.4 

 54.5 

 54 

 53 

 52 

 50 

 49 

 48 

 46 



Cu.ft. 



Bd.ft. 



Bd.ft. 



[ 50 



85 

 85 

 70 

 55 

 55 

 50 

 40 

 40 

 35 

 30 

 30 

 25 







60 



| 70 



80 

 89 

 94 

 100 

 108 

 115 

 123 

 132 

 141 

 148 

 156 



140 



80... 



130 



90 



150 



100 



no 



120 



130 



140 



150 



180 

 180 

 220 

 240 

 260 

 240 



1 160 



280 







1 Includes all trees 3 inches and over in diameter, breast high. 



2 Includes all trees 7 inches and over in diameter, breast high. 

 8 To a 6-inch top diameter limit. 



NORMAL STANDS. 



Normal stands are those which at maturity give the maximum yield 

 possible to obtain under a given method on a given quality site. In 

 the case of lodgepole pine properly or normally stocked stands are 

 rare. Eeconnaissance data, covering many thousands of acres of 

 young growth in Montana, show that nearly 80 per cent of the area 

 is overstocked, and that on the average the young growth is from one- 

 half to six-tenths normally stocked. Because of its slow mortality 

 lodgepole must start in comparatively open stands in order to yield 

 the maximum amount of merchantable material at maturity. Such 

 stands, however, are not dense enough to insure rapid, natural prun- 

 ing. As already pointed out, the number of trees per acre adopted 

 as the criterion of normality is 1,000 at 10 years, 500 at 30 years, 300 at 

 90 years, and 250 at 140 years. With these figures as a guide, and tak- 

 ing into account the total yield of the stand, Table 9 has been con- 

 structed from the figures obtained from those plots in Table 8 on 

 which the stocking appeared to be most nearly normal. The amount 

 of data is not sufficient to make the table anything more than indica- 

 tive of what may be expected from normal stands of different ages on 

 the best and on average sites. The original figures were secured on 

 quality I sites, and the yields for quality II sites have been derived by 



