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Show TREES CONSERVE SOIlTwatEf"' 1 Windbreaks Prevent Excessive EvaBa ration In Dry Lantf Areas G00(1 on the P-'ains. A hedge fifteen to eighteen feet high will lessen the evaporation of 6(y moisture in its vicinity. On the iti ward side the evaporation of moistmj in lessened to a considerable distant, i from the hedge and close up to th5 windbreak on the windward side. Th ! influence of the hedge on the evapora" ' tion of soil moisture depends up0n t i humidity, temperature, velocity of tt, ! wind, and kind and condition of th '' soil. At a distance of 200 feet from the leeward side of the hedge thU in fiuence falls off, but not rapidly. On ' the windward side the loss from evap. oration is less at 50 feet than at 200 ot 300 feet and lowest at 100 feet, prcb- ably due to the checking of the wind ' on approaching the hedge. The hedge has a greater influence in retaining soil moisture in fine, sandy loam than 1 in silt loam, but not at such a great i distance from the hedge. ' These facts were brought out In an experiment carried on in 1910 by ! Wilbur Zacharias, a senior in the Kansas Agricultural college. This ! experiment was continued from Octo- ' ber 11 to November 22, or a period of 41 dayB. Observations were taken and cylinders of soil weighed every 2i hours. The windbreak in this experiment was an Osage orange hedge on the college farm. Mr. Zacharias, who did the work for his thesis, gave the most careful attention to the test The physics department of the college took temperature and wind velocity readings. From this experiment and other observations ob-servations made by F. H. King of Wisconsin and R. A. Emerson of the University of Nebraska, it is to be inferred in-ferred that hedges would be of great importance in the level plains region, where the hot, dry winds of the Bummer Bum-mer sweep across the prairies with a high wind velocity, and the evaporation evapora-tion of moisture is excessive. This Is not so necessary in moist, humid climates, but hedges or any forest trees of sufficient height and planted thick enough seem to be an effective means of bringing about a solution of the conservation of soil moisture In the great plains region. |