I have had severe problems with brown patch fungus (Rhizoctonia species) the past two years. It killed almost 2/3 of my whole lawn last year and had to be reseeded. That cost me almost $700 for 200 pounds of new hybred perannial ryegrass seed. The fungus always crops up when the weather gets hot and humid. I only fertilize once in early Spring, which includes a pre-emergent, and once in the Fall in early October. Mach-3 insecticide is put down the middle of June for insect control for the entire growing season. I have also limed the lawn to keep the Ph neutral when necessary. I have had to put "High Yield" brand fungicide down twice this season, once in June and again now in early August, to stop the fungus. This is the only time I have watered the lawn to water-in the fungicide. I have learned that watering only spreads the fungus and makes the problem worse. Isn't there anything that I can treat the lawn with that will kill the spores and get rid of this fungus once and for all?? I'm at wits end!!