I believe what you are seeing is slime mold, Patti. It may be disturbing to see but actually does little real damage to your lawn. Chemical treatments are not necessary. A forceful spray from a garden hose, brushing with a broom, or use of a leaf rake all work well to disperse the powdery residue.
Ok! Whew! What a relief! Thanks again, Doug!! You're soo kind and helpful! I so much appreciate the fast response I get from you to answer my questions! THANK YOU!
I am also pleased to see this reply as I have been getting this once a year in my lawn/weeds for the last 4 years