What is this plant? This is slowly taking over my yard. You can see from one of the pictures that it's a vining plant of some sort. It will lay roots and then spread out. It came in to my yard a couple years ago from a bad batch of top soil and it's been spreading ever since.
Follow up question... how do I kill it? It did not respond to Scott's Weed and Feed. I've been pulling it out by hand and overseeding with grass, but it's a battle I'm losing. I need a better approach but I don't know what I'm up against.
For a climate reference, I live in western Pennsylvania.