Annual training once again is federally mandated in order to purchase and apply approved dicamba products (XtendiMax, Engenia, FeXapan and now Tavium) on Xtend (dicamba-tolerant) soybeans and cotton.
These products also have remained classified as restricted use pesticides (RUP), while all other dicamba products remained general use. Producers and applicators have to be certified applicators (private or commercial) and attend an annual dicamba training to purchase and use these products. Even if the applicator attended a dicamba training last year, they will have to attend the new training this year.
Oklahoma Cooperative Extension Service will be hosting several training events across the state this spring. Unfortunately, not many have been scheduled yet. Contact your local extension office, pesticide supplier or Oklahoma Department of Agriculture Food and Forestry (ODAFF) to find out when training will be held near you. Like last year, certified applicators will not receive a new card in the mail indicating they have completed the training. ODAFF will house a master list of applicators who have attended a training.
The product labels for the these dicamba products are in-depth and provide strict application and record-keeping requirements.
Required record-keeping, which must be generated in 72 hours, will include planting date. This is due to the fact that the labels now have restrictions for late-season applications. Late-season applications have a higher risk because that is when the crop is most susceptible to yield reductions due to drift.
In addition to the federal registration label, Oklahoma was approved for special local need labels for most of these products. A special local need registration, also known as a FIFRA Section 24(c) label, grants changes to the original federal registration label for the state it is approved.
For the state of Oklahoma, this Section 24(c) label allows for applications to be made up to 60 days after planting dicamba-tolerant soybeans, which is 15 days longer than the federal label.
Applications on soybean still have the restriction of not applying after the R1 growth stage (beginning bloom) regardless of the days after planting requirement. Applications can be made up to 90 days after planting dicamba-tolerant cotton, which is 30 days longer than the federal label. Applications can now be made from sunrise to sunset, which removed the one hour after sunrise to two hours before sunset restriction. These applications are allowed as long as there are no temperature inversions at the field level to reduce the risk of drift.
As a reminder, it is illegal to use other dicamba formulations on dicamba-tolerant soybeans and cotton. Only XtendiMax, Engenia, FeXapan and Tavium are allowed to be used over-the-top (post-emergence) on these tolerant cultivars.
This is because these formulations are far less likely to cause vapor drift and damage surrounding sensitive plants. Even though these products cost more than many generic dicamba products on the market, they also can be used in other applications, including pastures and many grass crops if drift is a concern.
Anyone interested in more information about dicamba-tolerant soybeans or cotton, upcoming dicamba training events or other Auxin tolerant traits like Enlist (2,4-D Choline) should contact their local Oklahoma Cooperative Extension Office.
Bushong is Oklahoma Cooperative Extension Service northwest area agronomy specialist.