268 



TIME CONSIDERATIONS 



and twenty years old, and one bare of all vegetation, are instrue- 

 tive. It will be observed that the average amount is appreciably 

 greater in the bare soil, and that the least amount is found 

 under forests 60 years old, when we may assume the trees are 

 in their prime. 





Spruce 



Uakkd Soil. 



Season 



120 Years Old 





16 inch 



32 inch 



Average 



16 inch 



82 inch 



Average 



Winter (January and Eebmary) . 

 Spring (March to May) .... 

 Summer (June to August) . . . 

 Pall (September to November) . . 



% 

 19.75 



17.47 



17.78 



14.88 



0/ 



/o 

 22.44 



20.83 



20.90 



19.46 



% 

 21.09 



19.15 



19.97 



17.17 



0/ 



/o 

 19.96 



20.66 



19.77 



20.04 



% 

 24.73 



20.51 



19.98 



20.20 



0/ 



/o 

 22.35 



20.68 



19.97 



20.12 



Other experiments have shown a marked difference in the 

 distribution of the water in the forest-covered and naked soils, 

 in the first-named a much larger proportion being held in the 

 extreme upper portion than in that which was unprotected. 

 This is a natural consequence of the absorptive properties of 



Average of Water Capacity, expressed in Percentages of the Weight 



OF the Soil 







Spritce 





TInriiaded 



Dbpth 



25 Years 



60 Years 



120 Years 



Soil 





Old 



Old 



Old 





to 2 inches 



30.93% 



29.48 % 



40.32% 



22.33 % 



6 to 8 inclies 



19.19 



18.99 



19.30 



20.62 



12 to 14 inches 



19.10 



16.07 



18.28 



20.54 



19 to 20 inches 



18.40 



1G.26 



20.16 



20.14 



30 to 32 inches 



17.91 



17.88 



21.11 



20.54 



the accumulated humus. The above table, as compiled by 

 Fernow^ from the work of Ebermayer, illustrates this point. 

 It is obvious that it is only that portion of the water which 



^ Bull. No. 7, forestry Division, TJ. S. Dept. of Agriculture, 1893. 



