| Show SPREADING WATER ON HILLS two systems 0 corrugation alon as demonstrated at the spokane congress one form of the corrugation fetn of irrigation as demonstrated at the congress Is applied to I 1 soil where the land slopes in more than one direction the ditches being made to follow the natural contour which needs no grading water Is supplied through one box and the ditches spread out in fan shape over the land another plan of the so called corrugation ru idea best adapted to sugar beet alfalfa and grain lands with a gentle slope showed water alon by means of V shaped ditches or rills 2 inches deep and about 18 inches apart the marginal dike or basin system of irrigation shows ditches built surrounding the tract 0 varying size running from one acre to ten acres in area to practice this method successfully the land must be level or have only a gentle slope sufficient head may be had in the water itself to cause it to spread ovea the ground |
