The Evaluation of Simulated 2,4-D and Dicamba Drift On Winter Canola in Oklahoma.

Winter canola (Brassica napus) is a valuable rotational crop for wheat producers in the southern plains and provides opportunity to improve control of some winter annual grass weed species; however, unintentional drift of herbicides in winter wheat and fallow fields may cause damage to winter canola, causing lower yields and decreased crop quality. This study was conducted to determine the effect of simulated 2,4-D and dicamba drift on winter canola seed yield, yield components, and seed oil quality when applied at various vegetative and reproductive growth stages.2,4-D ester and dicamba were applied at 0.5, 2.5, 5, 10, and 20% of the recommended use rates at either the 4-6 leaf stage (late-October), mid-flowering (mid-March), or late flower (April). Data collected included plant injury, fertile vs. infertile pods per square meter, branches per square meter, seed yield, and seed oil content. The results of this experiment will allow for development of recommendations for drift damage of phenoxy herbicides on winter canola.