Slime Mold On Grass. Give the affected area a good rake and mow the grass. Slime mold is fairly obvious.
Fungi in the genera Muctlaga and Physarium are usually the causal agents. Slime mold can appear in turf suddenly or overnight following a prolonged grass wetness. During warm and wet days in the summer slime mold can appear overnight.
The gunk may come back if ideal conditions still exist but it is easy to removealthough repetitious.
Give the affected area a good rake and mow the grass. Slime molds occasionally cause concern when they appear on lawns but they do not kill the grass. Identifying Slime Mold. You can also wipe it off with a broom or just mow over the afflicted blades.