3 indies in height growth per year, vhile ethers 

 on more racist slopes make from 6 to 12 .inches psr 

 year. All seedlings, however, make very blow 

 growth for the first three years until a deep and 

 firm root system is established. 



Counts of annual rings shovr that the 

 average tree is very slow in making diameter growth 

 until it is 50 or more years old, the average dia- 

 meter of JO year old trees "being less than 7 in- 

 ches. Another significant fact that has been ob- 

 served in counting the annual rings of Western 

 Yellow Pine stumps is that trees grown in the open, 

 even at low elevations, make a faster diameter 

 growth all through their natural life than trees 

 found in average stands on the higher and apparent- 

 ly more moist slopes. This increase in growth is 

 also' very pronounced in seedlings. By analyzing 

 seedlings grown three-quarters of a mile from the 

 edge of a treeless area, in a stand averaging 9 ** 

 feet 3. I'., 35 seedlings and 3 saplings per acre, 

 it was found that at an average age of 19 years the 

 seedlings were 1.57 inches in diameter at the ground 

 and 5.2p feet in height. Seedlings grown on the 

 border of a forest in a stand averaging 3 !- feet 

 3. I", and 400 seedlings per acre showed that at an 



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