AUGUSTA, Ark. - Scott Monfort was multitasking again. The University of Arkansas Division of Agriculture extension plant pathologist was guiding his truck around the potholes in yet another axle-breaking dirt road while running mental calculations on soybean rust worst-case scenarios.

He wasn't the only one having a rough ride.

As of Friday, the number of Arkansas counties with confirmed rust rose to 15, and for the first time this season, some of the counties were north of I-40. They are: Arkansas, Ashley, Chicot, Desha, Drew, Jefferson, Lee, Lincoln, Lonoke, Monroe, Phillips, Prairie, Pulaski, St. Francis, and Woodruff.

Rust can be devastating in any year, but if current cool, rainy conditions persist, the outcome could be bad with so many late-planted soybeans north of I-40.

According to the National Agricultural Statistics Service, Arkansas growers planted 3.4 million acres. Last year, the average state yield was 38 bushels per acre, which sold for $8.85 a bushel, for a value of about $1.09 billion, NASS said.

Should a worse case scenario appear for this year, "there might be a million acres of rust," he said. "If no one does anything to manage the rust, you could see up to a 30 percent reduction in yields."

Control has its costs too. "Let's say there are 500,000 acres that are ideal for rust growth, that need to be sprayed," he said. "If it's $15 an acre for the cost of chemicals and application, that's $7.5 million.

"It costs a lot to control the disease, but if conditions were perfect for rust and you don't control it, it's going to be a lot worse," he said.

Mother Nature seemed to be taking the rust's side, serving up a 20 percent to 50 percent chance of rain all Labor Day weekend, according to the National Weather Service offices at North Little Rock and Memphis, Tenn.

Monfort and the rest of the soybean team are issuing a conditional spray advisory for the 15 counties.

"This is not an automatic spray recommendation for all soybeans," Monfort said, adding there are specific criteria for soybean growers to check before spraying.

The good news is that much of the crop south of I-40 is looking good, extension agents for the University of Arkansas Division of Agriculture said.

For the latest information, call the Soybean Rust hotline at 1-866-641-1847.  If you have any questions or concerns please contact Monfort (870-659-0648) or Cliff Coker (870-723-5519).  For more information about checking for soybean rust visit www.aragriculture.org/diseases/Soybeans/Rust/
agent_questions.htm.

The Cooperative Extension Service is part of the University of Arkansas Division of Agriculture and offers its programs to all eligible persons regardless of race, color, national origin, religion, gender, age, disability, marital or veteran status, or any other legally protected status, and is an Affirmative Action/Equal Opportunity.