I noticed this hole in the exterior wall where the foam board insulation of the wall is exposed. Late last season I dug down a good 18" and still couldn't find the bottom of this hole. Tri-level home, this wall extends about 4ft below grade. Other walls of this room are normal grade; outside ground is at floor level.
Looking for feedback from the hive mind: this is probably rodents, ya? Wondering if I should totally excavate til I have all the damage visible, plug any varmint holes, and re-stucco(?) over the foam board. Or, if it's real nasty, I wonder if I'll need to replace a foam board panel entirely, then skim over the new nice flat surface with some sort of compound. There's a decent amount of foam missing.
That being said, is it even truly stucco? I have some ready-mix concrete patch compound that apparently dries somewhat flexible. I used that on a small crack on a different side of the house but not sure if it's the right stuff for the job. I doubt anything will ever color match, but it's better than having a hole in the wall.
Home built 1994. Upper Midwest.