Nitrogen fertilization and cover crop effects on soil structural stability and corn performance

Abstract

Abstract The effects of annual ryegrass (Lolium multiflorum L.), red clover (Trifolium pratense L.), and oilseed radish (Raphanus sativus L.) established in separate barley (Hordeum vulgare L.) and winter wheat (Triticum aestivum L.) plots which had received 0.5, 1.0, and 2.0 times the recommended nitrogen (N) rates (in Ontario) on soil structural stability and subsequent corn (Zea mays L.) growth and yield were investigated in field studies at Ayr and Woodstock, Ontario. Soil aggregate stability and corn growth and development were affected more by cover crops than applied N. Generally, aggregate stability was higher following cover crops than where no cover crops were used. Aggregate stability before spring tillage tended to be higher after oilseed radish than ryegrass and clover, a phenomenon which might be due to short‐term enrichment of soil stabilizing materials resulting from the over‐winter kill of oilseed radish and early decomposition. However, after spring chisel low, soil stability was higher ...