60 



F-igvcce 2. — Average net annuaZ 

 cubic volume growth per acre 

 follohrlng commercial 

 thinning. (Increments 

 connected by brackets 

 are not significantly 

 different, P < 0.05.) 



50 



40 



30 



< 



5 20 



10 



25 



49 



HEAVY 



53 



MODERATE CONTROL 



Table 2. -- Average annual diameter growth per tree for two 5-year 

 periods following cutting 



Treatment 



Periods following cutting 



1-5 years 



5-10 years 



Inches 



Heavy cut 

 Moderate cut 

 Control 



0.13 

 .12 

 . 11 



0. 16 

 .12 

 .08 



CONCLUSIONS 



This experiment was conducted to supply information which would help woodlot owners 

 decide what to do with their young merchantable ponderosa pine stands. Growth data from 

 the plots support the conclusion that a commercial thinning, removing about 30 percent 

 of the volume, can provide an immediate income and improve the quality of the residual 

 stand with no reduction in stand growth. Biologically, thinning presents an alternative 

 to liquidation cutting or no cutting. The woodlot owner should also consider other 

 factors such as future management plans for the tract, his need for immediate income, 

 alternative uses for the money invested in the timber stand, and market conditions 

 before choosing the alternative most beneficial to his particular situation. 



4 



