I can't believe this, but yesterday while weeding on the south side of my house, I came upon this little purple thing. I reach down and ouch, it's got thorns. Get a lower grip and a better grip and yank the sucker up. It was a volunteer jap barberry. I don't have jap barberries, but the house a block north of me does. I'm in small town USA, not on a large lot and here I've got a nice gift from a neighbor. So just because you live in suburbia, or a town like me surrounded by corn and beans, it does, and it will, spread.
Definitely popular in my father's nighborhood which is landscaped with them. Can you believe 3 berberis surrounding a pine tree in a semicircle at the far end of most of the houses. He lives in SC, and that is the common theme along with the overdone presence of a magnolia or crape mrytle as well.
escambiaguy, I'm not sure where Atmore is, I'm guessing zone 8b would make it farther down in your state, but what do I know. They had them in Chattanooga TN, zone 7a for sale, at the Lowe's, Home Depot and the like. We didn't live there long enough for me to hear if they had invaded forests, or peoples yards from other peoples yards for that matter. I hope nobody near you plants any of these. Because then you'll not only have that lovely privet you're trying to remove, but you'll have the barberry too.