Soil and water losses from plots planted to a corn, winter wheat, and lespedeza rotation were measured for 14 years. The plots, located on Grantsburg silt loam were 70 feet long and on slopes of 5% and 9%. During the period 1939–46, crop residues were removed or grazed from the plots. From 1947 through 1953, crop residues were returned to the plots. The average annual precipitation was 3 inches greater during the 1947–53 period than in the 1939–46 period. The maximum rainfall intensity (15-minute period) for the storms producing over 80% of the total soil loss was highly significantly greater during the 1947–53 period, when crop residues were returned, than in the 1939–46 period, when crop residues were removed. Comparable individual storms that produced over 80% of the total soil loss were analyzed for each of the two periods. Soil loss “per inch of rain” from corn plots was over three times greater when residues were removed than when they were returned on both the 5% and 9% slopes. Soil loss “per inch of rain” from winter wheat plots on the 5% slope was 3.9 times greater, and on the 9% slope 2.4 times greater when the residues were removed than when they were returned. During the 1947–53 period, soil losses from winter wheat plots were more than 2 times greater from 9% slopes and over 3 times greater from 5% slopes than from similar plots planted to corn. Crop residues on the surface reduced soil losses but did not materially change the amount of runoff from soils having a very slowly permeable subsoil. Data from individual storms producing over 80% of the total soil loss from winter wheat plots for the 1939–53 period were analyzed by the multiple regression method. The partial regression coefficient was determined between soil loss per inch of precipitation and rainfall intensity in inches per hour for the most intense 15-minute period. Keeping the variables of antecedent rainfall and total precipitation constant, the analysis indicated significant differences (1) between the rate of soil loss on 9% slopes where residues were returned as compared to where they were removed, and (2) between the rate of soil loss on 5% slopes as compared to 9% slopes where all residues were removed.

SynopsisTwo generations of Cheyenne winter wheat selections had highly correlated growth rates when the seed was germinated under drouthy conditions. D-mannitol solutions at 7 and 11 atmospheres tension were used to create the controlled drouth.

SynopsisStem and leaf breakage were the major types of injury from frost heaving to 14-day old seedlings of Hardinggrass, Perennial ryegrass, and 2 winter wheats. The lower the injury on the plant, the less the chance for survival. Ryegrass was more resistant than Hardinggrass at plant lifts less than 10 mm. Wheats were more resistant than the grasses. Depth of planting adversely affected grass seedlings at a greater degree than with wheat, but shallower planting caused greater root injury than deep planting in both grasses and wheats.