New to groundhog trapping

Got my name out for nuisance trapping for coon and coyote. Got a call the other day about a groundhog job. I've only accidentally caught groundhogs and never tried to specifically target them. I know apples and fruit in a live trap work. Just bought a 2 door live trap for this. The gentleman says there's only 1 hole under his deck, and thinks he's only seen 1 woodchuck, and it's a chunk. He has a brick over the hole currently. Can someone give me a quick lowdown on these creatures. There can't just be one entrance, right? Looking to place the 2 door trap in front of the hole. Any help and tips would be greatly appreciated. Thank you.

The two door will work. Put it up tight to the crawl under. Block sides so the chuck can't squeeze by. I like to use 3 cages covering the hole just in case there are more than one. Positive set, you don't need bait. Bait will attract non targets.

I'm a big fan of Comstock traps for groundhogs/woodchucks. I use either a nosecone over the hole forcing them through the trap or as Brian said, a couple of traps. Comstock has a three way splitter that allows you to set multiple traps at the same hole. There may or may not be another hole. A 9x11x24 trap is fine for groundhogs.

I'm another huge fan of the Comstock for groundhogs! They've paid for themselves several times.

I’m Im sure trap prices have gone up, but the first catch pays for the trap here.

i use marshmellows and that has worked better for me then fruit but you will catch nontarget animals I would take the double door and put it over the hole and fence it off so its a blindset but sometimes that's not possible so just do whatever works in your situation or maybe try a blindset and a baited set

Here is a photo from today. The fencing is not pretty but was effective.

The good thing about woodchucks is they don’t complain too loudly when the exclusion isn’t color coordinated with the deck.

Green apples work great in the back of a trap. there is a mulberry lure that works well too. But if you are going to use cage traps for groundhogs, keep them separate from other cage traps. the more groundhogs you catch in one and the more it smells like groundhog the better. There were times I used nothing in the cage trap and still caught groundhogs. If you catch an opossum or another animal, wash the trap before using it for a groundhog. If you can use a 160 BG, they work great. Don't be afraid to block off most of the area. Also you say you can not find the other hole/den, it may be on a neighbors property. They will move pretty far, especially mating season.
Also if the brick is still there from the home owner, then it's not a so called home, it's a stop over as he travels. If there are living in the den, that brick would be moved or they dig under or next to it within a day.

Attached are a couple more pictures using a comstock for ideas. This guy was living under the deck. No more.

How do you keep these (This word is unacceptable on Trapperman) coons out of your trap? Had apples in this one. And had lettuce with "woodchuck salad" on it the other day. This place is crawling with coons!

Don’t use bait. Posi set. The number of non targets you catch will drop like a rock.

To use TNADC’s example above, that animal has to either be going into or out of that belly rub (I’m assuming it’s a belly rub) under that deck skirt. If he used bait, anything that might pass by could be interested.

Using bait compensates for a trap that might not be in the right place.

160 conibear at the holes, no bait. You will occasionally catch possums and skunks as well as they will go down and use woodchuck dens. IF there isn't any pets in the area, then you have to screen or fence in the trap.