Some studies on the herbicidal properties of maleic hydrazide

Tests were conducted to improve the formulation of maleic hydrazide (MH) with respect to absorption and to add to its lethal action. It was found that surfactants and humectants intensify the effects of MH, that water-soluble forms are more effective than oil carriers, and that high humidity promotes absorption. Effectiveness, as judged by extent of regrowth, was also increased somewhat by after-treatments with toxic aromatic oils, repeated sprays of MH, follow-up applications of sodium chlorate, and simulated tillage treatments performed several days after spraying. Disturbance of plants two months after treatment, however, seemed to break dormancy. MH-induced dormancy was more prolonged in old, well-established Bermudagrass cultures than in new ones; however, MH sprays on annual grass cultures at different stages of maturity proved that young plants showed more injury than old ones.