Schultz Bruce, Webster, Eric P., Saichuk, John K., Groth, Donald E.
FENTON, La. – Rice growers heard advice from a range of LSU AgCenter experts Tuesday (May 26) during the southwest rice field day.
The event was held at research and demonstration plots on the farms of Jimmy Hoppe and Mark Pousson.
In one piece of advice, LSU AgCenter weed scientist Dr. Eric Webster said farmers should consider using ammonium sulfate to lower the pH of water used for mixing herbicides.
Webster said lower pH often will increase the activity of some herbicides, but some products can lower the pH to levels that could affect equipment. He said he prefers a pH in the neighborhood of 5.5.
Webster said he is doing work this year with the Ricebeaux herbicide as a possible alternative to Arrosolo, which will not be legal to use after this year. He said sales of Arrosolo were stopped last year.
Webster also cautioned farmers that medium-grain rice varieties and hybrids are more sensitive to injury from some herbicides.
“That’s why we always use two-x rates in our studies, to simulate overlap,” Webster said.
He said he recently viewed a field that had been planted in hybrids for three consecutive years. The volunteer rice from last year was widespread, he said, and that increases the possibility of outcrossing of herbicide resistance.
“There’s really only one choice – Roundup – and start all over and probably plant beans,” Webster said.
Farmers should start thinking about fungicide applications, said LSU AgCenter plant pathologist Dr. Don Groth. He said growers should consider the selection, amount and timing of the application.
The boot stage is the best time for fungicides to be used against sheath blight, Groth said.
Dr. Johnny Saichuk, LSU AgCenter rice specialist, said sheath blight has been found already this year in fields in Acadia Parish.
“If you are in green ring or beyond, you need to be looking for sheath blight,” Saichuk said.
Saichuk said the weather has caused problems for north Louisiana farmers. He said rains have prevented some from finishing critical work, and a few have not yet finished planting.
The LSU AgCenter and the LSU College of Agriculture