The challenge of resistant weeds is nothing new for farmers, but addressing it continues to keep them on their toes. Evolving species, changing markets, updated best management practices and new technologies mean growers need to be strategic to stay one step ahead of resistant weeds.
“To say that a robust weed management plan is important is frankly underplaying its significance,” says Tim Gardner, Market Development Agronomist with Bayer. “Not everybody is at the same stage when it comes to resistance issues on their farm, but no matter where they are they can work to not let it get a foothold.”
The ‘Four Rs’ in nutrient management are a well-known concept – using the right source, at the right rate in the right place and the right time. Gardner argues that those same principles can be used when it comes to herbicide application to manage for weed resistance.
“You want to use the right mode of action to manage resistant weeds,” he says. “You want to make sure you are applying your herbicide at a killing rate. You want to make sure you are targeting the source and spraying when the weeds are small and growing to effectively eliminate the weeds.”
Ashley Smith, Crop Protection Western Canada Marketing Manager with Bayer, agrees with Gardner’s 4R analogy, but says she might also add in another factor.
“The fifth ‘R’ in herbicide application is the right chemical rotation,” she says. “Are you layering in active ingredients to make sure you are not relying on a single herbicide, or a single mode of action in order to protect the molecule long term?”
Smith adds that before applying a herbicide, there are measures to take to ensure a crop is competitive from the start. That includes diverse crop rotations, targeted fertility plans and seeding at the proper depth and rate for good crop establishment during the critical weed-free period.
“Reflecting back on the previous season is just as important as planning forward,” Smith says. “Considering all of the different cropping systems and what has been in your specific rotation – what weed pressures have you seen and how easy or difficult have they been to control.”
A new tool to combat herbicide-resistant weeds
New Varro® FX is a cross-spectrum herbicide with Group 2 and Group 4 active ingredients. As the first emulsifiable concentrate (EC) on the market in Western Canada, it gives growers the freedom to easily and effectively tackle tough-to-control grass weeds like Group 1-resistant wild oats as well as providing a broadleaf weed control boost for cleavers, kochia and more. When mixed with tank mix partners such as Buctril® M herbicide, Thumper® herbicide and Infinity® herbicide – it controls all problematic broadleaf and grassy weeds for Prairie growers and offers chemical group diversity.
“A big part of weed resistance management is having a vision of your long-term goals,” says Rory Cranston, North American Market Development Manager, Cereals and Pulse Crops for Bayer. “You need to know your enemy and have a plan for three, four or more years down the line in your rotation. You need to think beyond your herbicide to set your crop up for success.”
Cranston says that Group 1 is used so commonly across the Prairies in canola and pulses and on about 60 percent of cereal crops for a good reason. It is effective, safe and easy to apply. Varro FX now opens the door for growers who are experiencing higher Group 1 resistance but who have shied away from Group 2 products because the formulations have been challenging in the past.
“With a product like Varro FX there are the unrecognized benefits of an easy-to-use formulation, and that comes in time savings,” he says. “If you are saving minutes in each tank you are loading and mixing – that gets you out quicker and earlier when weeds are small. Weed control is a game of time and you are limited in terms of weather and hours. A simple-to-use formulation is a benefit of a product that also gives you that added flexibility in chemistry rotation.”
For more information on Varro FX, visit VarroFX.ca or contact your local Bayer representative.
100 years, 100 farmers, 100 questions
Will we continue to control weeds or will weeds control us in the next century? This was one of the questions posed to 100 farmers as part of The Western Producer 100th Anniversary Market Research Project.
We are partnering with sponsors such as Bayer Crop Science to offer a series of webinars which will present the answers and challenge participating farmers to offer their own insights from the field. Experts from the project itself and Bayer will be on hand to discuss specific questions.
Join us online by registering for the first event on Thursday, March 21.
