You can't keep other candidates from 'poaching on your turf'. [=from trying to get voters who usually vote for you or your party to vote for them]
In chapter two, the author is on unfamiliar 'turf'. [=is dealing with an unfamiliar subject]
Synthetic 'turf' was installed in the playing field instead of grass.
(..) to New York and now he's back. And I don't know what to do. So I'm not so sure if it's a better plan to fight him on our turf or his... but you saw what they did, what they can do. At least on his turf, he's not expecting it. So I say we take (..)2018 Avengers: Infinity War