By Dr. Mark Loux, OSU Extension Weed Specialist, adapted from C.O.R.N. 2020-38
The USEPA recently reapproved use of Engenia and XtendiMax on Xtend and XtendiFlex soybeans, with modifications to address concerns about off-target movement. Summary of current situation follows:
– While the previous labels for these products listed all of the typical uses of dicamba that are found on most dicamba labels aside from soybeans, these two products are now approved for use only on dicamba-resistant soybeans – Xtend and XtendiFlex.
– Can be applied preplant, preemergence, or postemergence: XtendiMax – up to R1 stage or no later than June 30, whichever occurs first; Engenia – no later than June 30. Emerged broadleaf weeds should be less than 4 inches in size.
– A maximum of two preplant/preemergence and two postemergence applications is allowed. Maximum XtendiMax use rate for any one application is 22 oz/A. Total XtendiMax allowed per season is 88 oz/A. Maximum Engenia rate for any one application is 12.8 oz/A. Total Engenia allowed per season is 51.2 oz/A.
– Apply in a minimum spray volume of 15 gpa with boom set no higher than 24 inches above target. Do not exceed a ground speed of 15 mph. Do not mix with AMS.
– XtendiMax: all applications must include an approved volatility reducing agent (VRA) such as a VaporGrip Xtra Agent product. Engenia: all applications must include an approved pH buffering adjuvant. See websites for list of approved products.
– Apply between one hour after sunrise and two hours before sunset when wind speed at boom height is between 3 and 10 mph. Do not apply during temperature inversion.
– Always maintain a 240-foot buffer between last treated row and downwind field edge. Roads, mowed grass and tolerant crops (e.g. corn, Xtend soybean, etc.) can be included in the buffer. Do not apply product if sensitive crops or certain plants are in an adjacent downwind field.
– Do not apply under conditions that favor runoff. Do not apply if soil is saturated with water or when rainfall that may cause runoff is forecast to occur within 48 hours.
– Users should be familiar with stewardship information on the product label and associated materials prior to use. Dicamba-specific training and proof of training is required prior to use of these products. The following websites, which contain information on approved nozzles and tank-mix partners, should be consulted prior to application: Engeniatankmix.com; xtendimaxapplicationrequirements.com. Do not mix any other product of any type with any dicamba product unless it is approved and listed on the website.
– FeXapan has not been reapproved at this time, but should be at some point in the future according to our sources. Tavium maintains its approval, with many of the same modifications in use outlined above. Tavium can be applied up to the V4 stage or June 30, whichever occurs first. Precautions and guidelines, and need for training, are similar to the dicamba products listed above. See label and the Tavium website for specific information on stewardship, mixtures, etc – TaviumTankMix.com