SOIL LOSSES BY WIND EROSION

Measurements of wind erosion from fields are limited, but with recently developed erosion samplers, it is possible to determine soil losses from natural winds. Erosion of soils by wind was measured in five states. The soil loss was dependent on wind velocity, storm duration, and soil surface characteristics. Average annual rainfall varied from 356 mm at Eads, CO, to 915 mm at Crown Point, IN. Field soil varied from 29% sand at Eads, CO, to 83% sand at Big Spring, TX. Soil losses from individual erosion events in 3.1-ha fields varied from 0.050 kg m(-2) at Big Spring, TX, to 7.007 kg m(-2) at Elkhart, KS. Soil surface roughness, percentage of wind-erodible aggregates on the soil surface, and percentage of the soil surface covered with nonerodible material such as crop residues are extremely important in controlling wind erosion. A ground cover of 4% reduced wind erosion losses 15% compared with bare soil. Ridging a smooth soil with 50- to 70-mm ridges reduced soil erosion 98% on a sandy loam soil.