Weed Issues Shift with Row Rice

Growing rice in the Mid-South often involves multiple production systems, each with its unique benefits and weed control challenges. Meeting those challenges requires flexibility and strategy to ensure lasting protection from weeds ranging from barnyardgrass and sedges to Palmer amaranth.

“Bolero®, League®, Regiment® and Regiment® EZ Herbicides can be used in row rice, drill-seeded rice and water-seeded rice,” says Frank Carey, senior manager of field research and development for Valent U.S.A. “You’ve got the flexibility to mix and match our herbicides with what you’re seeing in the field and the cultural practices that growers want to use.”

In recent years, the popularity of furrow-irrigated rice, also known as row rice, has grown exponentially.

“You've got three zones in row rice,” Carey says. “You've got the, the upper zone where it's dry, more like upland rice, and that middle zone where it kind of stays wet all the time. And then at the bottom of the field, it's basically back to flooded paddy rice.”

With three distinct environments and varying water levels, weed challenges can differ from one end of the field to the other, especially where soil is exposed. In a traditional flood system, controlling weeds before the flood is of paramount concern. Then, weed control, except for aquatic weeds, is aided by the water.

“We don't really have a lot of Palmer amaranth issues in flooded rice, whereas in row rice we do because that soil is exposed and the flood is not keeping the Palmer amaranth down,” says Mallory Scott, field market development specialist for Valent U.S.A. “With row rice, we have the weeds of soybean production, if you will, and the weeds of rice production.”

With a wider variety of weed challenges in a row rice production system, overlapping herbicide residual activity is crucial to controlling weeds in exposed soil.

“Unlike the flooded rice situation, we have exposed soil in row rice production and there's even more of a need to overlap residuals,” says Scott.

Valent’s preemergence herbicides - League and Bolero - are two residual herbicide options that fit well into a row rice production system.

“We hear the phrase overlapping residuals a lot when we're talking about weeds that are difficult to control,” Carey says. “Every opportunity you get, put a residual in there as well.”

For more information about the rice herbicide portfolio from Valent U.S.A., visit Valent.com, or contact your local retailer or Valent U.S.A. representative.