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Show WHN THE WATER IS WASTED Deep-Furrow Irrigation Does Net Solve Problem of Even Distribution k Teet at Riverside. Furrow Irrigation, wherever it caa be practiced, is gradually supplanting other methods. In tank experiments it was shown that furrows, by reduo-i reduo-i ing evaporation, cauae a larger quantity quan-tity of water to enter and stay in the ! soli than does the basin method, and it was further shown that the loss of water was smaller as the depth of the furrow Increased. Moreover, small ' quantities of water frequently applied , showed a much larger loss than heavy Irrigations applied at longer Intervals and followed by thorough cultivation. Though deep-furrow irrigation aoema most efficiently to aolve the problem, of how to got the largest quantity of , water Into the soli, it does not solve the problem of even distribution unless un-less the Irrigator thinks bard and In vestlgates closely. In order to de terrain the course, progress and dls trlbutlon of irrigation water in the soli, a deep trench eighty feet long was dug across sixteen irrigation furrows fur-rows and four tree rows in a Riverside River-side orange orchard with loose, sandy loam soil, wooden troughs conveying the water over the trench during the Investigations. The work was carried on by Dr. R. II. taughrtdge of the University of California, under the direction di-rection of the bureau of irrigation investigations. in-vestigations. Upon the race of this trench the darkening color of the soil made it possible to determine accurately the downward and outward percolation of the water from the furrows. The six teen furrows were made In eight pairs, the pairs being separated from each other by irregular distances, three feet being the minimum and ten feet the maximum. Unexpected results re-sults were obtained by a study of the water distribution. The water from only two pairs of furrows was found to have united. Between Be-tween the moist acres underneath the other seven pairs strips of dry soil were found. Furthermore, It was discovered dis-covered that the downward spread of the water decreased as the depth advanced, ad-vanced, giving the moist area a conical con-ical appearance, with the apex of the cone directly beneath the furrow, its base being wldeat about a foot beneath be-neath the surface. Upon more com psct soli types similar conditions prevailed, pre-vailed, except that the water traveled laterally at a slightly greater rate and In several cases showed a maximum downward penetration of only three feet In three daya. Despite the greater great-er lateral movement the space in the center of the tree row was usually found to be dry. |