i8o 



Forestry Quarterly. 



Table II. 



Influence of Root Competition in a Plantation of Three-Year 

 White Pine Transplants. 



387 



242 



This table indicates that root competition caused an increase 

 in the loss of 10% for the unshaded trees and of 20% for the 

 shaded. It also emphasizes the importance of the shade factor, 

 since we have the same general trend toward higher percentages 

 alive with increase in shade- Medium or heavy low shade with 

 root competition appears to have been preferable to no shade 

 and no root competition. 



A portion of the Brooks plantation had so heavy a ground 

 cover of pine and hemlock needles and twigs from the cut oflF 

 stand that there was no vegetation of any sort on the area when 

 the planting was done. There was no shade. Grass and mullein 

 started during the summer on the mineral soil exposed by dig- 

 ging the mattock holes, and their roots were the only competitors 

 of the planted seedlings. The loss was very heavy, due partly 

 to the stock (3-0) used. Of 231 without root competition, only 

 53 (22.9%) were alive; and of 214 with root competition, only 

 36 (16.9%) were alive. The strong influence of this root compe- 

 tition from herbaceous plants is best expressed by saying that 

 for every three trees which successfully withstood both drouth 

 and competition, a fourth would be alive had the latter factor 

 been absent. 



In the inspection of the Harvard plantation, a separate record 



