For those planning on planting dicamba tolerant crops next year, there is plenty of change coming in 2018 compared to last year.
The label requirements for spraying will be much different and training is being required for applicators.
“The new labels for Engenia, XtendiMax, and FeXapan have many new precautions that applicators need to be aware of,” said Mark Loux, Ohio State University Extension herbicide specialist. “An additional requirement is that anyone applying these products must attend an annual dicamba or group 4 herbicide-specific training.”
In 2017, there were 27 official complaints of dicamba damage with the Ohio Department of Agriculture. The U.S. EPA is monitoring complaint reports and the label changes in 2018 to determine whether to continue to allow post- application of dicamba.
The label changes will make the already narrow application window in 2017 even narrower in 2018. At Purdue University, Joe Ikley and Bill Johnson took a look at the potential window of opportunity for dicamba application last year based on 2017 label requirements. Here is an excerpt from their report.
We decided to take a look at hourly weather data from the Agronomy Center for Research and Education (ACRE) near West Lafayette to see how many hours we could have applied Xtendimax or FeXapan to Xtend soybeans in June and July at that location.
We first looked at rainfall data to determine how many days in each month that equipment traffic would not be possible on the farm. In addition to eliminating the days where equipment traffic was not possible, we removed the 24-hour period leading up to rainfall events since the Xtendimax and FeXapan labels do not allow applications of the product when rain is forecast within the next 24 hours. Once we removed the hours and days where we could not spray due to soil conditions or label restrictions with regard to forecast rainfall, we examined hourly wind conditions to determine how many hours we could apply these approved dicamba products.
Xtendimax and FeXapan do not allow applications of the product when wind speeds are below 3 MPH or above 15 MPH. Using these parameters, we looked at hourly weather data to determine when the average wind speeds allowed applications. When combing over the data, we noticed that there were several hours with wind gusts well over 15 MPH. With this in mind, we further refined that data to calculate hours when wind speeds were between 3 and 15 MPH, including wind gusts, which we called “ideal” spray hours. We chose these products because without access to actual temperature inversion data, it would be more difficult to retroactively calculate Engenia application hours. Engenia will allow applications with wind speeds under 3 MPH, but places the responsibility on the applicator to confirm no temperature inversion is present.
When we added up all the sprayable hours in June, we found that we could apply Xtendimax and FeXapan for 334 hours in June (46% of the month). We calculated 184 ideal spray hours in June (26% of the month)…We ultimately came up with 13 days in June where we could not apply these products, 13 days with at least 8 ideal spray hours, and 4 marginal days in the month of June.
July ended up being less windy than June was, yet we ended up with fewer spray hours. Many nights in July had wind speeds below 3 MPH, making applications off-label at those hours. When we totaled the hours up, we had 267 spray hours in July (36% of the month), and 250 ideal spray hours (34% of the month). If we were to factor in the cut-off of applications once soybeans reach the R2 growth stage, many fields would have considerably fewer spray hours in July as crops progressed through early reproductive stages.
There are numerous training opportunities for applicators in Ohio during the next few weeks. Here are some of them compiled by Ohio State University Extension.
• January 17, 2018 9-11 am OR 2-4 pm, Sponsored by BASF
Clinton County Fairgrounds Expo Bldg
958 W. Main Street, Wilmington, OH 45177
• January 25, 2018 9-11 am OR 2-4 pm, Sponsored by BASF
Findlay Hilton Garden Inn
1050 Interstate Dr. W., Findlay, OH 45840
• January 25, 2018 9-10:30 am OR 2-3:30 pm, Sponsored by Monsanto
OARDC Fisher Auditorium
1680 Madison Avenue, Wooster OH 44691
• February 13, 2018 9-10:30 am OR 2-3:30 pm, Sponsored by Monsanto
445 South Jefferson Avenue, Plain City, OH 43064
• February 19, 2018 9-10:30 am OR 2-3:30 pm, Sponsored by Monsanto
Holiday Inn Express
2150 East Wooster, Bowling Green, OH 43402
• February 20, 2018 9-11 am OR 2-4 pm, Sponsored by BASF
445 S. Jefferson Ave., Plain City, OH 43064
• February 27, 2018 9-10:30 am OR 2-3:30 pm, Sponsored by Monsanto
1920 Roschman Avenue, Lima, OH 45804
Dupont is also offering training at http://www.dupont.com/products-and-services/crop-protection/soybean-protection/products/fexapan.html. The online module, product label and stewardship guidelines for use of FeXapan plus VaporGrip Technology are available at FeXapan.dupont.com. In addition, farmers can visit FexapanApplicationRequirements
In addition to the training events, Ohio State University, Purdue, and the University of Illinois put together a fact sheet on stewardship of dicamba, which is available here. This is not meant to be an all-inclusive list of application requirements, but it does contain some additional suggestions on stewardship that are not part of labels.