Is this allium vineale / wild garlic? Allium oleraceum / field garlic? Or Allium schoenoprasum / #chives?
The last option, chives, is #native to the USA and #PA; the others aren't. I'm growing a native plant garden, so if it's #invasive / introduced, I'll evict it.
When I picked a leaf off the specimen growing out of the wall, it smelled faintly of green #onions, so I'm inclined to believe it is in the onion family.