I noticed the otherday at one of my accounts two bluish colored rings about 6 inches in diameter they appeared to be some type of fungus and they are located under a oak tree. The account called today to inquire what it was and wants it treated if its something serious. I would post a photo but my disk drive is on the blink and I cant load my digital camera program into the puter. I can't locate any summer disease that resembles this in my turf/pest control book. Any help would be appreciated.