Nick Hustedde knows a few things about battling tough weeds. He’s a technical sales representative for FMC, based in Effingham, Ill. In 2018 he visited soybean plots near Sheridan, Ind., where FMC tested various products and cultural practices. Since it was the first year at the site, the company didn’t know what to expect in terms of weed pressure.
“There was significant pressure here for some weeds,” Hustedde says. “We certainly could demonstrate how various concepts and products work to customers and retail dealers.”
He says the three toughest weeds many farmers battle today are marestail, giant ragweed and tall waterhemp, followed closely by lambsquarters. It’s possible to control them, he notes, but it takes attention to detail, season in and season out, year in and year out.
Here are five keys to staying ahead of weeds from Hustedde:
1. Use best management methods possible. “You’ve got to start the season clean, and stay clean,” Hustedde says. That means finding a herbicide system that works well for you and staying with it.
It may also mean using cultural practices to help with weed control. For example, narrow rows allow soybeans to canopy more quickly and help shade out late-germinating weeds.
2. Make scouting part of your weed control plan. Scouting helps in multiple ways, Hustedde says. First, you need to know which weeds are in the field. One issue for the FMC crew planning weed control at this new site was that they didn’t have prior knowledge of which weeds were most prevalent. You need to know which weeds are in each field to know which herbicides to select and what rates to apply.
Second, scout to detect weeds when they’re small. Especially if you’re using a herbicide like Liberty, you need to catch weeds when they’re small to be effective. Spraying a 2- to 3-inch-tall weed is much different than spraying a 4- to 6-inch-tall weed, Hustedde says.
3. Choose herbicides with multiple sites of action. Trying to knock out tough weeds, many of which can develop resistance to herbicides, is more difficult if you don’t go after them with herbicides that kill weeds in different ways. Understand which classes of herbicides use various modes and sites of action for killing weeds. Mix up your approach to include herbicides with various sites of action, Hustedde advises. That’s one of the best ways to prevent developing further weed resistance.
4. Don’t try to spray your way to prosperity! You may break the bank before you whip the weeds, Hustedde says. While preventing soil erosion is crucial, you may have mechanical options to aid in weed control, especially on level fields, he says. Consider other methods besides strictly applying herbicides.
5. Minimize weed seed production. You should have zero tolerance for weed escapes, Hustedde says. Even weeds that are burned back by a postemergence spray but not killed may later go to seed, particularly tough weeds such as waterhemp. In fields where you no-till and use cover crops, cereal rye could help smother weeds such as marestail in the spring, minimizing potential weed escapes.