Soybean rust has now been reported in two North Carolina counties, located along the South Carolina border. Rust appears to be making its way slowly north, with weather conditions the next few weeks moderate to high for development.
In North Carolina, over 90 percent of the State’s 1.6 million acres are beyond the R5 growth stage and are not in danger from soybean rust. Remaining beans are scattered and growers should look at local forecast and finds to determine whether spraying is an option.
The latest finds, reported on Sept. 19, are in a commercial field. A previous find in an adjoining county was in a sentinel plot. In both finds, infection levels were low. In the latest find, only one leaf out of 40 samples had rust infection.
Much like 2005, rust is likely to spread northward, with its rate of movement largely dependent on weather patterns. The rust is later occurring in 2006 and much of the acreage has been harvested.
Growers should be aware that spraying beans beyond the R5 growth stage is illegal, and that these sprayings will provide no yield advantage.
Rust was also reported in Baton Rouge parish in eastern Louisiana. As in the North Carolina finds, levels were low and most of the soybean crop has been harvested in the area.
Currently rust has been found infecting this year's soybeans in 40 different counties in eight states: Alabama, Florida, Georgia, Louisiana, Mississippi, South Carolina, Texas and North Carolina. Including reports on kudzu, there is a total of 60 counties in eight states with rust this year including 5 in Alabama; 13 in Florida; 14 in Louisiana; 10 in South Carolina; 11 in Georgia; 3 in Texas; and 2 in Mississippi and North Carolina