Management of Lodgepole Pine 175 



site quality, age and density. In the case of Lodgepole density is 

 of exceedingly great importance. Several sample acres of hun- 

 dred-year-old Lodgepole were taken on sites of the best quality, 

 the stands varying in density from 500 to 1,800 stems per acre. 

 A maximum yield of about 20,000 board feet was secured with 

 about 800 stems, the yield falling off rapidly to less than L500 

 board feet when the number of stems increased to 1,800. The 

 data for the plots show a similar effect upon the cubic foot yield 

 of the stand, and upon the average height and diameter of the 

 trees. In one case a 70-year-old stand was observed on a site of 

 at least average quality, in which there were slightly over 100,- 

 000 green "trees" per acre, averaging about 4 feet high and less 

 than a half inch in diameter at the ground. The stand had com- 

 pletely stagnated. 



The average yield for merchantable stands, which are ordi- 

 narily from 100 to 200 years old, is from 5,000 to 8,000 board feet 

 per acre, scaling to a minimum diameter of 6 inches in the top ; 

 when the average stand is scaled to only 8 inches in the top the 

 yield is reduced by almost one-half. Timber sale areas in the 

 Lodgepole region usually yield about twice as much as the aver- 

 age merchantable stands, for the sales are usually located in the 

 heaviest timber. Maximum stands on single acres vary from 

 24,000 to 36,000 board feet. The heaviest acre recorded is one 

 on the Deerlodge Forest in Montana, which, at 200 years, con- 

 tained 36,000 board feet of green Lodgepole, 4,600 feet of other 

 green timber, and 8,000 feet of dead Lodgepole — a total of 48,600 

 feet on the acre. 



Thinnings are decidedly beneficial in Lodgepole stands. Meas- 

 urements taken in stands ranging in age from 50 to 150 years, 

 thinned from 15 to 25 years ago, due to incomplete logging opera- 

 tions, removing, on the average, slightly more than half of the 

 cubic foot volume of the stand, show that the majority of the 

 trees left standing have increased considerably in their rate of 

 growth. In most cases the total amount of wood produced per 

 acre since the thinning is as much, if not more, than would have 

 been produced if the stand had been left unthinned, and the wood 

 so produced is decidedly more valuable since it is distributed upon 

 fewer stems. If accidental thinnings made by loggers give such 



