Brown spot, caused by the fungus Septoria glycines, is present in all soybean fields in Kentucky. In most years the disease causes little to no yield impact; however, up to 15% yield losses can occur in select environments. For example, brown sport tends to be worse where soybeans follow no-till soybeans, where early-maturing varieties are planted, and/or when fields are planted in late April. River bottom fields or fields subject to fog or morning shade are frequently impacted.