Good morning Sandy!  Thank you for submitting the sample photographs.  Is the area where you shot the photographs the only spot where the infestation occurs?  Are there any tress or shrubs in the area with an infestation?  Are you able to drop a sample of the insect by the Extension office?  If not, could you send a picture of a a closer view?

My initial thought is the infestation is some type of caterpillar.  For now, just continue to sweep them up.  Likely, the problem will be short-lived.

Thanks-Jeff