Published online by Cambridge University Press: 12 June 2017
Numerous investigations in which crop plants were utilized to study the effect, persistence, and movement of spray residues of 2,4–dichlorophenoxyacetic acid (2, 4–D) in a variety of soils and under a wide range of conditions have been reported. However, except for a report by Arle (1), a search of the literature has revealed no direct information on the effects of 2,4–D when applied in irrigation water to crop plants growing in the field. Arle treated cotton with irrigation water containing 2,4–D in equivalents ranging from 0.5 to 8 pounds per acre. Significant decreases in yield usually resulted from the higher rates of treatment when applications were made early in the season. Applications at the lower rates usually resulted in yields about equal to or greater than those obtained from check plots.