Looks like a washing machine threw up on my St. Augustine. I am assuming it is some form of fungus. It is hard, kind of pukey white, is about 1-2 inches thick, and is spreading. It started in the grass, and is now trying to climb the tree. Any help on how to treat it is welcomed. It isn't killing the grass, but if you pry this stuff off the ground, it pulls the runners up with it, and the ground under it is berift of life.