However, infected roots either die or become dysfunctional during the hot, dry summer months. Root growth is inhibited by high soil temperatures, and plants cannot rapidly replace diseased roots. Infected plants are no longer able to supply adequate water to the foliage and the plant dies. Circular patch symptoms develop because the fungus tends to grow radially out from a central infection point. The fungus can survive many years in the soil, and symptoms often develop yearly in the same location.
Summer patch is an extremely difficult disease to control.
Several cultural practices will help suppress disease development. Turfgrass should be maintained in a vigorous, but not overstimulated, growing condition. A balanced fertilization program is important. Avoid excessive nitrogen fertilization during the summer months. Seventy-five percent of the nitrogen fertilizer should be applied in the fall.