TIMBER; FORESTRY 353 



Regulation of the water supply is, however, the most 

 important service which forests render, aside from their 

 value as sources of timber. It is a matter of common 

 observation that when a wooded region is stripped of its 

 trees, brooks and rivers are subject to violent floods in the 

 season of heaviest rain or at the melting of the snows, 

 while during the drier months springs fail and streams 

 run low, so that their beds may be only a series of pools. 

 These facts are due to the regulative effect of the forest 

 floor on the distribution of water which falls as rain or 

 snow. On bare ground, not even covered with grass, a 

 large portion of the rainfall is at once carried off to the 

 nearest streams. Even on grasslands the run-off is rapid, 

 as is shown by the quick rise of praiiie rivers after a heavy 

 rain. But the leaf-covered forest floor, often carpeted 

 with moss, holds water like a sponge and continues to de- 

 liver it for many days after every heavy rain or period of 

 melting snow. This gradual delivery of water, part of it 

 draining off along the surface, part of it soaking into the 

 soil and then slowly finding its way underground into 

 springs and streams, makes the watercourses of a heavily 

 forested region comparatively permanent and constant, de- 

 livering considerable water at all seasons of the year and 

 rarely overflowing their banks within a few hours after 

 rains. For this reason it is of the utmost importance that 

 wooded regions like the White Mountains, the Adiron- 

 dacks, the central and southern portions of the Appala- 

 chian system in which many streams have their sources, 

 should be protected by appropriate legislation as soon as 

 they are seriously threatened by the lumberman. 



