The study on which this analysis is based was concerned with the socio-economic factors that prevented erosion control in western Iowa from coinciding with goals of erosion-control programs. Information was obtained by personal interview from 138 farm operators and 49 nonoperating owners of farms in the area in 1957 in a continuing investigation of the obstacles preventing adoption of erosion-control practices and of possible remedies for these obstacles. The same sample of farms had been included in two previous studies in 1949 and 1952. Data from these three studies were used to analyze the effects of changes in obstacles to erosion control on changes in soil loss.

The average estimated annual soil loss for the sample decreased from 21.1 to 14.1 tons per acre from 1949-57. In an effort to determine why the 5- ton-per-acre goal of public programs in the area had not been attained in 1957, multiple variable linear regression was used to analyze the relationships between obstacles, farm characteristics and soil losses. The statistically significant obstacles preventing the reduction of soil losses by farm operators were (1) operators' need for immediate income, (2) their failure to see the need for recommended practices (custom and inertia) and (3) field and road layout of the farms. Characteristics which explained a significant amount of variation in the estimated soil loss were (1) topography of the farm, (2) soil conservation district participation, (3) the operator's ability to borrow funds for erosion-control practices, (4) days of off-farm work and (5) recognition of the seriousness of the erosioncontr01 problem by farm operators. While not statistically significant, the most important obstacles for nonoperating landowners were (1) need for immediate income and (2) insufficient roughage-consuming livestock on tenant-operated farms.