The turf is best defined by this passage from The House of God:
"What's a TURF?" asked Potts.
"To TURF is to get rid of, to get off your service and onto another, or out of the House altogether. Key concept. It's the main form of treatment in medicine. Just call up psychiatry, tell them about the Nazi stuff, don't mention the gut pain, and presto - TURF TO PSYCHIATRY." Ripping up the index card containing the Nazi seeker and throwing the bits over his shoulder, the Fat Man said, "The TURF, I love it. Let's go. Next?"