By Eric Anderson
The Environmental Protection Agency has added specific requirements for pesticide applicators when spraying new dicamba products in soybean.
As was discussed in Part 1 of this two-part article series, “Spraying dicamba in Xtend soybeans in 2018? Be sure you meet all the requirements,” the ability to spray a broadleaf crop with dicamba to control difficult broadleaf weed species represents both a powerful tool for weed management and a source of concern regarding off-target plant injury. The Environmental Protection Agency (EPA) has categorized the new dicamba products as restricted use pesticides (RUPs) and has also added specific restrictions on using these products.
The following is a brief description of the requirements. However, it is critical you read the most current version of the herbicide label—remember, the label is the law—before you spray. Also, check the Xtendimax, FeXapan or Engenia websites for more information, as some of the information on these “living labels” is only available online. Following these guidelines will not only reduce the risk of off-target injury and help you maintain good relationships with your neighbors, it is the law and is required for using these dicamba products.
- Mandatory training. The following states are conducting their own mandatory training: Alabama, Georgia, Indiana, Missouri, Mississippi, North Carolina and Tennessee. For those not applying in one of those states, the training may be conducted by a third party (e.g., Extension, a local retailer, one of the three registrants selling the approved dicamba products). For example, Monsanto is holding several training events in Michigan in February and March of 2018 including morning and afternoon sessions, and BASF will hold training events on March 16 in Battle Creek, Michigan. Check with your local seed or agricultural chemical representative for more options.
- Certification and recordkeeping. Applicators must be certified by their state’s department of agriculture, and records of each application must be logged within 14 days of application and kept for a period of two years due to the RUP status of the products.
- Application rate. Apply only at the application rate specified on the label.
- Application timing. Apply only during daylight hours and never during a temperature inversion. Some states (not Michigan at the writing of this article) have elected to be more restrictive with time of day, so contact your state’s department of agriculture prior to spraying.
- Downwind buffer. When applying the labeled rate, maintain a 110-foot buffer between the crop being sprayed and any sensitive areas, including tree lines, ditches with native vegetation, fields with susceptible crops, etc. Do not apply when the wind is blowing toward an adjacent susceptible crop.
- Wind speed. Apply when the wind speed is 3-10 mph.
- Tank mixes and adjuvants. When applying with other pesticides or crop products, only spray each respective dicamba product in tank-mixes with approved products. Check the label and website of the given product for an up-to-date list. DO NOT use ammonium sulfate (AMS) as an additive, as this will increase the volatility of the herbicide.
- Spray volume. Apply these products in a minimum of 15 gallons of spray solution per acre.
- Approved nozzles. Use only nozzles approved for each product and only within the range of specified pressures. Check the label and website of the given product for an up-to-date list. The droplet size should be extra course to reduce the chances of drift.
- Ground speed. Do not exceed 15 mph when applying, as this will increase the risk of drift.
- Boom height. Maintain the spray boom height at no more than 24 inches above the target weeds or crop canopy. Greater heights will result in increased potential for drift. No aerial spraying is allowed.
- Clean spray equipment. It is critical that all spray equipment be thoroughly cleaned before and after use to remove dicamba residue. Even very low rates of dicamba can cause injury when applied to very sensitive crops.