Asian soybean rust (SBR) caused by Phakopsora pachyrhizi was discovered for the first time in the continental United States in November 2004. It was known that under the right conditions, this pathogen could spread rapidly and cause severe yield losses. There are no resistant soybean varieties available, and management requires proper timing of fungicide treatments. In addition to the impact of the disease itself, there are concerns that producers would be tempted to treat their fields unnecessarily before the fungus was present in their area, making their treatments ineffective and increasing the costs of production.