Date of this Version
Thesis (M.S.)—University of Nebraska—Lincoln, 1951. Department of Agronomy.
The object of this study was to try to determine the effect of different cropping systems on runoff and erosion, with special reference to the effect of biennial sweetclover, not only during its period in the rotation, but also in the remaining years of the rotation.
Runoff and erosion data obtained during the period were limited in nature, not because precipitation was below normal, but partly because intensities were never great. The two plots, having sweetclover growing, allowed very little runoff, apparently giving complete protection to the soil under the conditions encountered during the period. A small amount of runoff and erosion were obtained from the six plots having corn, oats, and wheat following two years of sweetclover. The plots lost runoff in the order corn—oats—wheat, with the amounts of each under the sub-tillage treatment being 0.02 inches runoff or less. In comparing the plowed plants of each crop, the one that was plowed suffered more runoff and a greater amount of erosion than the sub-tilled member.
A series of soil moisture samples taken at one foot levels to ten feet on the grain rotation plots showed greatest moisture in the profile under sub-tilled with residue. The least moisture was in the plot that was plowed with residues removed, with the plot that was plowed with residues being intermediate.
Advisor: F. L. Duley.