THE ROLE OF ASPEN IN REFORESTATION 



257 



TABLE 2 

 Soil moisture on planting plots 



CH.\.n.\CTER OP PLOT 



NUMBER 

 PLOT 



SOIL MOISTURE, PER CENT OF DRY WEIGHT 



June 8 



Open. . 

 Aspen. 



Open. 



Average. 

 Aspen 



Average. 



1912 Planting 



17 



May 24 



O 

 10 



37.2 

 21.7 



29.5 



38.7 

 35.4 



37.5 



June 21 



18.9 

 14.4 



16.6 



24.1 

 24.3 



24.2 



July 19 



15.9 

 11.3 



13.6 



11.9 

 12.9 



12.4 



Aug. 16 



16.7 

 14.9 



15.8 



14.3 

 15.5 



14.9 



1913 Planting 



Sept. 20 



7.9 

 5.4 



6.6 



7.9 

 9.2 



8.6 



Open. 



Average . 

 Aspen 



Average. 



the open than under the aspen. This appears to be due partly 

 to subsurface seepage in the open plots from higher ground in 

 the near vicinity, and partly to the fact that the ground is prac- 

 tically bare of native vegetation as a result of heavy grazing 

 previous to fencing in 1913. 



The varying relation between the aspen-covered and open 

 plots in 1912 when samples were taken monthly through the 

 growing season is explained as follows: Practically no rain fell 

 in May, June and the first half of July. At the beginning of the 



