SALEM, Ohio — This year, farmers using dicamba herbicides, XtendiMax, FeXapan and Engenia, will see significantly new label requirements for the 2018 growing season.
These requirements come after hundreds of farmers not using dicamba resistant Xtend soybeans in the Midwest and South last year experienced damage from dicamba drifting from neighboring fields.
The Environmental Protection Agency (EPA) worked with states, cooperative extension agents and the pesticide manufacturers to develop solutions to minimize the potential for these damages to happen again in the 2018 growing season.
Certification. Farmers must become certified to apply the three restricted use dicamba herbicides: XtendiMax, FeXapan and Engenia.
Timing. The 2018 labels restrict farmers from applying during certain times of the day. South Dakota State University Extension recommends avoiding spraying from sunset to sunrise and one hour after sunrise and one hour before sunset to avoid inversion.
Inversion occurs when cold air close to the ground is trapped by a layer of warmer air, causing those fog- or mist-like layers you see in late spring or summer as temperatures start to rise. Dicamba particles can drift into those inversion layers and be carried from field to field.
Related: Volatility plays a big role in dicamba drift
Wind speed. Do not apply when wind speeds are at 10 mph or higher to reduce potential drift or when wind speeds are below 3 mph to avoid inversions.
Rainfall. These products cannot be sprayed if rain is in the 24-hour forecast.
Record keeping. Farmers must maintain specific records regarding the use of dicamba, such as air temperature (avoid spraying in high temperatures), wind speed, vehicle speed during application (never apply products at speeds over 15 mph and over 5 mph on field edges), and time of day applied.
Commercial applicators must retain records of all applications for three years, and private applicators must retain records of restricted use pesticide applications for two years.
Tank clean-out. Make sure any tanks carrying dicamba mixes are thoroughly cleaned out before and after use.
Mixes and nozzles. Use only approved mixes and carefully check the label of each product for mix order. Only use nozzles approved and listed on the label for these products.
Scout the field. Assess your fields before application to determine whether some should be treated with dicamba based on sensitive surroundings, Mark Loux, Ohio State professor and Extension specialist, said in an Extension C.O.R.N. newsletter.
Some sensitive crops and vegetation include non-dicamba tolerant crops, gardens, organic crops, fruit trees, vineyards, ornamentals and tree rows. Never spray without a 110- to 220-foot buffer as specified on the label.
And pay close attention to all labels on herbicides and pesticides, not just the dicamba products.
