Compaction and the Surface Structure of a Poorly Drained Soil
ABSTRACT THE surface structure of the poorly drained soils of southwestern Ontario has deteriorated to a level which is considered to limit corn and soybean productivity. The contribution of vehicle compaction to surface soil structural deterioration on these soils has not been shown. Therefore, a 3-year experiment was conducted to determine the cumulative contribution of surface soil compaction to soil structural deterioration and its relationship to corn and soybean productivity on a poorly drained clay loam soil. Fall vehicle compaction, at soil moisture contents suitable for tillage, of the surface soil did not significantly contribute to soil structural deterioration and did not limit the productivity of corn and soybean grown in a corn-soybean-corn rotation. However, fall compaction did significantly restrict early to mid-season plant development. Spring compaction generally contributed to soil structural deterioration and limited productivity. There were no cumulative detrimental effects of fall or spring compaction on soil structure, plant development, or yield over the duration of this experiment.