I do exactly as below - probe and recover if shallow enough, trap door plug if deeper than a few inches. Always with an electronic pinpointer in hand. The pinpointer is what tells me the item is shallow enough to probe for. If the pinpointer can’t hit it, time for a plug. I try to never plug in turf unless the ground is moist, which can really limit me to spring and fall in Reno. Or areas that have great sprinkler systems.