Rice growers should be on the lookout for rice water weevils

by Nick Bateman - May 28, 2024

We’re getting a fair amount of calls on rice water weevils from Stuttgart up through Jonesboro. It’s hard to say if these are higher than normal populations or if we just have so few fields going to flood attracting adults. Over the next week or after the next dry spell there will be more rice going to flood and that will tell the story of this year’s pressure.

As our fields go to flood, we need to be on the lookout for adults. Scarring on leaves will show if adults are present, but scarring isn’t the best indicator of population levels. We can take a sweep net out, do a set of ten sweeps about 50 to 60 feet away from bar-ditches, and that will give us an idea of the rice water weevil population present.

For rice that is treated with Cruiser or NipsIt, those give us about 28 days of residual. We’re not at zero control after 28 days, but there’s a pretty good reduction there. Rice treated with Dermacor or Fortenza will still have protection 60 days after planting.

Foliar insecticide options include Lambda-Cy, Warrior II or similar products. Belay is also an option, but it does have a third tiller cut off so it may be out for many dealing with rice water weevils post-flood. We have about five to seven days after the flood is established to get maximum control of rice water weevils with a foliar insecticide – which is why we need to be chasing the flood and scouting these fields. After that, our only method of control is draining the field until the soil cracks, costing us more money in weed control, fertilizer and re-flooding.

Insecticide recommendations for rice in Arkansas can be found in the MP144.