AFTON - Asian Soybean Rust has been discovered in a field near Afton making Ottawa County the northernmost county in the United States to have a confirmed case of the potentially devastating fungus.

Stan Fimple, Oklahoma State University extension agent in Miami, said the rust was confirmed Friday on one of 100 leaves he had submitted for testing.

Fimple is participating with extension agents throughout the United States in gathering weekly samples from sentinenta plots in an effort at early detection of the rust. The testing also tracks the south to north spread of the fungus.

Rust has previously been detected in five other Oklahoma counties. Those counties include Atoka and Bryant counties in southern Oklahoma. Rust has re-emerged in Choctaw County after a weeks absence.

Rust was detected in Payne County, but was not found there in the most recent testing. Rust is also present in Tulsa County. Rust, which is spread by the wind, has also been found in Texas, Alabama, Arkansas, Florida, Georgia, Louisiana and Mississippi this year.

Oklahoma Department of Agriculture officials recommend spraying fungicides to protect soybeans from rest where plants have reached the flowering stage and have abundant vegetative growth.