Farming requires careful planning, especially when costly investments are on the line. Spraying herbicides is just one example of the balancing act producers face when making decisions. So how do you get the best bang for your buck?
A good herbicide plan is dependent on several variables: what weeds will be targeted, what crop will be treated, and what type of application will be used? When is the best time to spray, and how can you best hit your target? With so many elements – many of which are dependent on one another – it’s crucial for growers to be as informed as possible. But as Dave Kloppenburg and Jeff Loessin from Corteva Agriscience advise, a combined approach of best practices and products will provide the greatest return on your investment.
When and where to spray
Deciding when to spray is just one piece of the puzzle, and even the best-laid plans have elements beyond a grower’s control. “Have a plan for the season – and that would include a Plan A, a Plan B and a Plan C,” advises Kloppenburg, the category leader for corn and soybean herbicides in Canada for Corteva Agriscience. “You can’t control the weather; you have to have a good plan and backup plans if the weather doesn’t co-operate.”
“From a timing perspective, generally speaking, early is always better than late,” he adds, advising producers to err on the early side of the product label for many reasons, including reducing competitive pressures of the weeds on the crop. “Tackle the fields with heavy weed pressure with early programs, and place an emphasis on pre-emergent herbicides.”
Loessin, the category leader for corn, soybean, cereal and forage seed for Corteva Agriscience in Canada, says following up in-crop will be based on many factors: “The best weed control is always achieved when weeds are small and actively growing,” he notes. The stage of crop is important as well, and this will vary depending on what crop is being grown, and how competitive or vulnerable the crop is.
Spraying can put a lot of demands on growers who are balancing their workload with making sure that labels are followed while at the same time optimizing herbicide performance. Recent research trials have shown that nighttime spraying may not be ideal. Many products are showing better performance when sprayed during daytime hours.
Meeting all the right targets
Proper stewardship of herbicides is important and the use of herbicides should be managed in conjunction with a greater integrated pest management strategy. Enlist Duo herbicide from Corteva Agriscience is best used as part of a program approach in Enlist E3 soybeans and Enlist corn, using additional herbicides to control weeds, which will help to improve weed control, reduce weed competition and manage herbicide resistance.
“We recommend the use of burndown herbicides with residual activity and different groups that provide a base level of weed control, when the crop is getting established,” Loessin says. “Then the farmer has some flexibility to make the decision regarding the post-emergent herbicide application, including what to spray and when.”
Kloppenburg advises being aware of what’s going on in your neighbourhood, too. “Are growers in neighbouring fields growing herbicide-sensitive crops? Ensure your sprayer is properly calibrated, and take extra caution to the product label if the wind is blowing in the direction of the sensitive crop. This includes following the label with regard to buffer zones.”
Despite a grower’s best efforts, spray drift can occur when particle drift from an application does not hit the intended target. Though some off-target movement is inevitable, there are ways to minimize spray drift, such as spraying at low wind speeds (as per the product label), setting the proper boom height above the spray canopy, and using the appropriate nozzles. The recommended boom height when spraying Enlist Duo is no more than 60 centimetres above the crop or the ground, and the wind speed should be between three and 16 kilometres per hour.
When combining these strategies with the drift control technology found in Enlist Duo, physical drift risk is reduced even further. Enlist Duo has Colex-D technology, which limits the risk of physical drift by helping to control the droplet size into a range that is less susceptible to physical drift. The formulation also has near-zero volatility.
“We’ve done what we can, from a formulation standpoint, to make sure that we minimize physical drift by putting in a drift-reduction component, and we’ve made sure the volatility is minimized so we don’t end up with vapour off-target movement,” Kloppenburg adds. “Both of those things work together to ensure the herbicide goes where it is intended to go, and stays put. But there’s also an onus on the farmer to make sure that the application is necessary and warranted.”
That’s the bottom line, Loessin agrees. “The grower still has to use good management following the label as far as the wind speed, boom height, correct choice of nozzle,” he says, noting user-friendly products still require proper application and management. “Only with that will we have complete success as far as on-target applications.”