Beating a Tough Competitor | The More You Grow | Corteva Agrisciences
 6/16/2022

Beating a Tough Competitor

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Top view of kochia in cereal grain field

Where other plants wilt, kochia thrives, especially in gritty, inhospitable conditions.

“The more tough and drier the conditions, the more kochia thrives,” says Ken Munson, agronomy manager for Beulah Farmers Union Oil in Beulah, North Dakota. “Kochia thrives in almost every situation, and it is the only thing that grows well in a drought situation without crop canopy and competition from other plants and weeds.”

Munson witnessed that firsthand in recent years when the northern Plains experienced severe drought. In addition, windy conditions helped spread weed seed, especially kochia.

“In 2021, the wheat got about a foot tall and headed out,” he says. “We didn’t have the crop competition and canopy in 2021, which increased kochia pressure and likely increased the spread of kochia seed.”

Even under those difficult conditions, Munson was impressed with the performance of Rezuvant® herbicide with Arylex® active on kochia.

“We had phenomenal results with Rezuvant. We didn’t get crop canopy. And with a normal rainfall of 17 to 20 inches of rain, 2021 was the second year in a row when we only got 5 to 8 inches of rain. Two years of drought is tough to overcome,” Munson says. “Rezuvant worked, kept the fields clean, and achieving kochia control was huge.”

He tank-mixed Rezuvant with an 8-ounce rate of MCPA ester to pick up Russian thistle. Rezuvant may be applied from two-leaf to flag leaf emergence, offering farmers a wide application window.

“The best time to kill kochia is from emergence to when it reaches 2 to 3 inches tall. After that, it has a good hold and is hard to kill,” Munson says. “We have so much resistant kochia in our area that we have to get a second site of action in the tank.”

In Munson’s view, Rezuvant shines because it lacks the carryover issues inherent with other herbicides.

“With Rezuvant, the only rotation you worry about is lentils, and that is not an issue in my area. You are wide open on your rotation options with Rezuvant,” Munson says. “Rezuvant is an all-in-one product for grasses and broadleaf weeds. You just throw it in the tank and you are ready to go.”

Munson is hoping the cereal crops in his area will fare better in 2022. Moisture this spring has improved compared with spring 2021.

“We have more soil moisture to plant in than we had the past two springs. We still need timely rains to maintain soil moisture and avoid plant stress,” Munson says.

In addition to kochia, major weeds that Munson’s farmers are battling include green and yellow foxtail (pigeon grass), Persian darnel, marestail, wild buckwheat and Canada thistle. Narrowleaf hawksbeard also is becoming more prevalent.

“Narrowsleaf hawksbeard is working its way southeast and can be controlled fairly easily with a fall burndown. But if you don’t get it in the fall, you can have quite the problem come spring when it can quickly take over a field,” Munson says. “Starane Flex does a good job on hawksbeard.”

For marestail control, Munson generally recommends Rezuvant. Canada thistle and wild buckwheat infestations trigger Munson to recommend WideARmatch® herbicide from Munson.

“Hitting weeds when they are young is the key to control. The smaller they are, the easier they are to kill,” Munson says. “A smaller plant that hasn’t hardened off, if sprayed when temperatures are cooler, will generally be easier to control.”

Visit Rezuvant to learn how you can win the battle against kochia and other troublesome weeds.

OpenSky®, Rezuvant®, Starane® Flex and WideARmatch® are not registered for sale or use in all states. Contact your state pesticide regulatory agency to determine if a product is registered for sale or use in your state. Arylex® is a registered active ingredient. Always read and follow label directions

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