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had its natural leai" and litter covering..^ And it was found that the burned 

 over plot, on which the litter and other vegetative cover had been destroyed, 

 lost last year 80 times as i'auch of the rainfall by run-off as the plot of 

 similar soil and slope which had not been burned. 



That was certainly striking evidence of the great water holding 

 capacity of the unburned forest floor, but the specialist in charge of 

 the work was skeptical about the leaf litter being responsible for all 

 that difference. 



Mr. Bennett tells me that all the leaf litter from a measured square 

 of that forest floor was gathered up, and put in barrels of water. Having 

 soaked up all the water it would, the material was then weighed. This done, 

 the litter was carefully dried and weighed again. Of course, the difference 

 in weight represented roughly the entire weight of water the litter had beeu 

 able to soak up. 



Well, the expert got busy with pencil and paper and figured out on 

 that basis how much water could have been held by the litter covering that 

 test plot of forest land. And he found the total amount way, way short 

 of the amount which the measurements had shown to have remained on the land. 



It didn' t take long to solve the mystery. If the water retained was 

 not in the litter, it must be in the ground under the litter. Just as much 

 rain had fallen on the burned-over plot and the soil, the slope and forest 

 cover were the same for both plots. When the bare plot was dug into it was 

 round that the water had soakred in only a little way below the surface. 

 Digging down into the soil under the litter-covered forest floor, it was 

 discovered that the water had permeated down, far, far down into the earth. 

 That natural forested area had absorbed 100 tons of rain per acre more than 

 the burned-over land. 



Why, you may ask, did the water sink in on the leaf covered soil 

 and not on the same kind of soil which lacked cover? 



Well, an old irrigation farmer uiight give you the clue to that. 

 He would probably know from e3cperience that some soils won't soak up muddy 

 water readily. 



What really happens, Mr. Bennett says, is that silt in the muddy 

 water actually seals up the pores in the soil so that the moisture can't 

 percolate furtlier into the ground. Rain falling upon the bared forest floor 

 quickly washes up soil, then the muddy water clogs the tiny channels which 

 would let clear water into the ground. In other words the big thing the 

 forest litter does is to act as both a physical protector of the soil and as 

 a tremendous filter to keep the water free of silt and let it sink into the 

 ground. 



In the forest leaves and litter, in the prairie or open country 

 grass and bushes serve to check the flow of water and their accumulated 

 refuse to filter this so that clear water can sink into the soil. Some of 

 our older men, who can remember back to the early conditions in our Prairie 

 States before farming cane in on a cig scale, say that the matted turf of 

 the prairies in many places hung like canopies over the banks of streams. 

 And those streams carried clear water the year around. Even if in some 

 cases those stories have to be salted down a bit, it is still evident that 



