Dollar Spot Lawn Disease
Dollar spot is caused by the fungus, Sclerotinia homeocarpa. It causes straw-colored spots about the size of a silver dollar (2 to 6 inches diameter) to appear on closely mowed turf. Grass in affected areas may die and the spots may merge to form larger, irregular patches. In coarse textured grass that is cut high, the dead spots are larger and more diffuse. Leaf blades have light tan spots with reddish-brown margins that develop across the leaves. Early in the morning you may be able to see a cobweb-like growth of the fungus over the infected area.
Dollar spot most commonly occurs on bermudagrass, zoysiagrass, bentgrass, fescue and ryegrass. Dollar spot is most active from late spring through fall. The fungus develops during humid weather, when daytime temperatures are warm (59 to 86 °F) and nights are fairly cool. These conditions result in heavy dew forming on the grass.
Prevention and Treatment
Proper cultural practices (e.g. irrigation, mowing and fertilization) will help prevent dollar spot disease. If thatch is more than ½ inch the lawn should be de-thatched to remove excess. Fungicide may be necessary for control. Your Fairway Lawns technician can determine if a fungicide treatment plan is necessary.