This fungus produces white, gray or purple patches in the lawn that are usually visible in the morning. They are also noticeable later in their life cycle when they cause grayish or black crust-like powdery balls on blades of grass. Slime molds come in a variety of colors, including brown, salmon, off-white, yellow, orange or brick red. They occur mostly during the spring during warm, wet conditions and may occur in the same location each year. Although they may look alarming, slime molds pose no harm to lawn grasses.
Slime molds feed on bacteria, other fungi and decaying organic matter in the soil.
They do not feed on green plants. Slime molds grow on dead organic matter and therefore do not pose a direct threat to any plants in the garden. Excessive shading and an undesirable appearance of the lawn can occur when fungal growth becomes very heavy. Control of slime molds is not necessary, since they do not pose a threat to any plants in the garden. The slime molds will disappear in dry weather.