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Show FOREST SOUS HOLD MOKE WATER THAN OPEN SOILS Soils m forested areas will absorb more water and will hold it longer than the soils in open areas unprotected unprotect-ed by any kind of vegetation, says the Forest Service of the United States Department of Agriculture. In the formulation of any comprehensive and long-term plans for the control of floods, it is declared, it is important that this fact be considered and that the scientific data on the relation of forests to soil water be thoroughly reviewed. re-viewed. Notable among the studies which have demonstrated the absorptive and retaining power of areas covered with ! forest, is the investigation made by Trof. I. T. Bode of the Department of Forestry. Iowa State College. Pro-fe.vsor Pro-fe.vsor Bode made his study on four small sites in the "Backbone" State Park. Delaware County, Iowa. Two of these sites had heavy timber growth, witli a good layer of forest litter lit-ter and decaying leaves, while the other two had boon denuded of Umber. I It was found that the average content con-tent of water of the soils in the tim-I tim-I bor-covered area as well as both maxi-j maxi-j mum nnd minimum contents were above those for soils on the unprotected unprotect-ed area. The soils on the timber-covered area were of n more sandy nature than those on the unprotected area in the sites selected. The greater nbsorp-i nbsorp-i the power of the soils In the area ! covered with timber was apparent, while the run-off of rainfall was found to be greater on the open slopes. I Investigations of the seepage of soil j water on these sites showed that this was most, rapid on the open slopes following fol-lowing a rain, while the seepage was greater In quantity, steadier, nnd distributed dis-tributed throughout a longer period of time in the area covered with timber. tim-ber. By thus absorbing more water, by holding it longer nnd by allowing It to seep out more gradually, niea.s covered cov-ered with forest cxx-rt n considerable Influence In the regulation of streiim-riow. streiim-riow. tending to prevent high water nnd Hooding following periods of heavy rninfall on the one hand, nnd drying up of streams during the dry sen'.ons on the other. Win e in even n limited men the rr-movnl rr-movnl of the forest cover from one of the slopes had such a marked of reel., says the ForoM Service, the influence of foi-esl.H over largo ureas in maintaining main-taining more uniform steam flow must be reminded n mi exceedingly tmix.it- |