The effect of alfalfa on soil moisture
1929
Duley, F.L.
1. At the Kansas Experiment Station soil moisture determinations to a depth of 10 feet have been made during the seasons of 1926 to 1928 on upland that has been in alfalfa since 1910 and also on land in a 16-year rotation including 4 years of alfalfa. 2. When alfalfa was on the land the moisture content of the deep subsoil was reduced to a low point and remained almost constant. 3. With most of the rainfall coming during the growing season, the moisture penetrated very slightly below a depth of 6 feet. The crop used the moisture about as fast as it came. 4. When alfalfa land in the 16-year rotation was broken and kept in corn and wheat for 10 years, the deep subsoil failed to gain materially in moisture. 5. When a field in alfalfa for 18 years was broken out June 6, 1928, and fallowed until August, both the soil and the deep subsoil gained rapidly in moisture, whereas other land carrying a crop made no gain during this period. This would tend to emphasize the value of at least a short period of fallowing to conserve moisture for getting alfalfa started.
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