I have had good luck with a Havahart trap when there is a groundhog or rabbit in the greenhouse. An apple core usually works fine for bait. I wash the trap thoroughly by total submersion before I release the critter.
I have also had good luck getting groundhogs to move out by filling their entrances with fresh dog feces. I think this works because fox often take over groundhog burrows.
I have also had good luck getting groundhogs to move out by filling their entrances with fresh dog feces. I think this works because fox often take over groundhog burrows.