Gray leaf spot alert

This observation from the past applies to current conditions. The high temperatures and high humidities that promote gray leaf spot (GLS) epidemics have been prevalent for several weeks around the U.S. Yet the dreaded disease, which is caused by the fungus Magnaporthe grisea, has only surfaced recently. So why are we seeing a delay between conducive weather conditions and the appearance of the disease?

a possible answer is that superintendents who have been hit with GLS before have been on…