Field Infiltration Studies With Green Manures and Crop Residues on Irrigated Soils

Abstract The effects of leguminous and gramineous green manure crops and corn and cotton crop residues on soil structure were compared by measuring water infiltration rates in irrigation furrows. Experiments were performed on alluvial soils of widely varying texture, developed in a Mediter‐ranean‐type climate. Gramineous summer and winter green manures improved infiltration relative to fallow. This benefit was restricted to soils of medium and fine textures. The effectiveness of barley green manure increased as it advanced in maturity. Neither summer nor winter annual legumes influenced infiltration. Corn crop residue and, to a lesser extent, cotton crop residue were effective in improving infiltration. Corn roots alone also made a significant, but lesser, contribution to improved infiltration.