Movement of Triazine Herbicides and Metolachlor in a Sandy Soil

The movement of atrazine, cyanazine, simazine, and metolachlor was studied in an Evesboro loamy sand soil. Both no-tillage and conventional tillage treatments were used. Atrazine, simazine, cyanazine and metolachlor were applied pre-emergence at rates of 2.24, 2.24, 1.68 and 1.68 kg/ha, respectively. All four pesticides were detected in the ground water 9 days after they were applied. A total of 31.5 mm of rainfall occurred within the time period. Atrazine and simazine were detected more frequently than cyanazine or metolachlor in the ground water. Under no-tillage metolachlor was detected in the ground water the least frequent of the four pesticides. The soils data indicated all four pesticides moved to at least the 150 cm depth 15 days after they were applied. Pesticide concentrations were greater in the ground water and in the 30-150 cm soil profile depth under no-tillage than conventional tillage.