[ronb]

Dig them out; otherwise you will have sumacs back immediately. It's not that big a deal - 20 3" sumacs? that's 3 hours with a pitchfork and persuader bar to do the complete job. If you could pull them out with a chain & etc, you'd leave some root in which would then grow more back. And you'll be tearing the ground up around them and compacting soil, making it a lot harder to grow anything there in it's place. Even grass. While you're at it...don't plant mowable grass there...if you have sumacs, you have some water underneath, and you can plant all sorts of beautiful shrubs that like wet.