Name: greene Savannah, GA (Sunset 28) (Zone 8b) I have no use for internet bullies!
Old mulch, I never thought of that. If the former gardener/homeowner used edging they may well have used mulch and possibly some landscape fabric. Might be good to start digging here and there to see what you can discover hidden under the grass.
Sunset Zone 28, AHS Heat Zone 9, USDA zone 8b~"Leaf of Faith"