Leafy spurge control with picloram and various 2,4-D formulations was evaluated to determine the optimum treatment combination and carrier volume for aerial application using a microfoil boom. Leafy spurge control was similar when the same herbicide treatments were applied at 94 and 47 L/ha but declined at 23 L/ha. Leafy spurge control was better when similar herbicide treatments were applied with a one-row microfoil nozzle boom compared to a two-row nozzle. Leafy spurge control 12 months after treatment tended to be better with picloram at 0.28 and 0.56 kg ae/ha applied with 2,4-D mixed amine compared to picloram plus 2,4-D dimethylamine or oil-soluble amine formulations during average growing conditions. However, picloram plus 2,4-D oil-soluble amine was the best formulation in dry conditions.
