By Bernard Zanstra
Dry bulb onions are growing rapidly with the warm weather. Most are now in the flag to one true leaf stage. Weeds have germinated and are developing beyond the cotyledon stage. It is time to apply the first GoalTender (oxyfluorfen) treatment to kill emerged broadleaves. GoalTender is the water-based formulation of oxyfluorfen.
GoalTender may be applied to dry bulb onions when the onion plants have one fully developed true leaf and the second true leaf emerging. The first true leaf emerges after the flag leaf has straightened. In warm weather, onion plants develop rapidly from the flag to the two leaf stage. To kill emerged broadleaves, apply up to 4 fluid ounces (0.125 pounds active ingredient) of GoalTender. That rate will kill most broadleaf weeds in the cotyledon to two true leaf stage. Waiting until the onion two leaf stage allows the weeds to develop more and become more difficult to control.
It also is time to kill interplanted barley. Use the highest recommended rate of Fusilade, Poast or SelectMax to kill the barley completely. A second application of Prowl H2O may be included with the graminicide. A delay in killing the interplanted small grain in onions can result in stand thinning and yield reduction.