Fairy Ring—is caused by a number of species of mushroom-forming fungi. Visible signs of fairy ring disease are circular or semi-circular rings, usually darker in color than that of the surrounding turf grass, which form in the turf and may or may not produce mushrooms within those rings. These rings can range in size from a few inches up to many feet in diameter. Excessive thatch and turf grass growing in low fertility soils with insufficient irrigation appears to suffer more damage from fairy rings than turf grass with adequate fertility and irrigation. Weeds will commonly invade infested areas. A turf grass management program that provides proper fertilization and irrigation along with regular dethatching of the turf grass will help prevent the development of this disease. Fungicide treatment or soil removal may be necessary if fairy ring becomes a problem. NOTE: The presence of mushrooms alone does not mean that your lawn has fairy ring disease.