Farmers should be aware of the pH level in the water they use to mix insecticides, Dale Pollet, an LSU AgCenter entomologist, told growers at a sugarcane field day at the LSU AgCenter’s Iberia Research Station.

Pollet said a pH level of 5.5 to 6.5 is preferred. A higher pH can cause insecticides such as pyrethroids to break down more quickly.

Pollet said it is not uncommon for water pH to increase during periods of hot, dry weather as Louisiana farmers experienced recently.

Pollet said armyworms should be expected this time of year, but it’s likely their natural enemies will take care of any invasion.

“Don’t waste your time and money spraying for them.”

Brenda Tubana, a researcher in the LSU AgCenter School of Plant, Environmental and Soil Sciences, said work is under way to perfect the use of the Greenseeker sensing device to determine nitrogen needs for sugarcane. The device scans sugarcane plants to determine the amount of biomass — or total amount of material — in a plant.

She said the LSU AgCenter will be conducting farm trials on the device.

Sugarcane farmers should consider growing soybeans in fallow years when they don’t have sugarcane growing in a field, said James Griffin, an LSU AgCenter weed scientist.

A soybean crop allows farmers to control weeds and offers the chance of making money from the beans. Soybeans have good potential on land that has been used for sugarcane because the soil usually is high in organic matter, he said.

Griffin warned farmers that weed resistance to the herbicide glyphosate may become an issue in Louisiana. He said johnsongrass that appears to be resistant has been found in Louisiana, and it’s possible bermudagrass could develop resistance.

Jeff Hoy, LSU AgCenter plant pathologist, said rust disease and smut are becoming problems in newer sugarcane varieties, including HoCP 96-540.

Variety resistance is the main strategy against rust, but farmers must understand varieties eventually will have problems with the disease.

“Rust is an adaptable organism,” Hoy said. “It can overcome resistance.”

A diverse range of varieties will help farmers deal with rust. Hoy said Brazilian sugarcane farmers have 12 to 15 varieties to choose among, and they have minimal rust problems.

Mike Pontif, an LSU AgCenter researcher at the LSU AgCenter’s Sugar Research Station, told farmers that the variety HoCP 96-540 accounts for 60 percent of the sugarcane planted in Louisiana. New varieties are in development, including Ho 00-950, which has proven to be the sweetest and shortest variety.

In addition to the field day, the LSU AgCenter held the 47th annual sugarcane field day at St. Martinville for sugarcane growers in St. Martin, Lafayette and St. Landry parishes.

Farmers at the St. Martinville field day got a look at a portable grinder, called the X-tractor, while it extracted juice from sugarcane in the field. During a demonstration, the device became clogged with cane.

“That’s why they call it research and development,” said inventor J. Roy of Lafayette, La. Roy will be making changes to the machinery, including more powerful engines. He said he’s been told that what he’s been trying to do would be impossible.

“I don’t buy that,” he said. “I like a good challenge.”

Jim Simon of the American Sugar Cane League told farmers that prices have increased slightly, and the amount of sugar imported into the United States from Mexico has declined because producers south of the border have no sugar to export.

Food processors are switching from fructose, made from corn, to cane sugar, he said. This increases domestic demand.

Simon urged growers to observe guidelines for burning cane fields. “All it takes is one messed-up burn to have a devastating effect on the industry.”

Al Guidry, LSU AgCenter county agent in St. Martin Parish, reminded farmers to keep written records of weather conditions during a burn to document wind direction and speed, among other details. He said burning should not be done at night, and a burning field should be watched until the fire is out.

Mike Strain, state commissioner of agriculture, said a bill was submitted to the legislature this year to outlaw prescribed burns in fields and forests. He said the measure failed, but it signals the need for caution.

“We need to police ourselves,” he told the farmers.

Strain said in a few years, the need for burning would be a thing of the past if energy production using biomass could be perfected.