Does anyone know of a good barrier to bury next to patio bricks to keep moles from burroughing under patio blocks and causing them to become unlevel? My neighbor has a problem with this. I've started helping him by trapping the moles (he let them go unchecked for several years). He has to redo his patio. While going to all the effort to pull, level, and re-lay patio bricks, I'm curious if anyone knows of a barrier that could be placed in the ground along the edge of a patio, to keep moles from undermining patio blocks.

Got a backhoe? I've seen mole runs eight foot down.

I have a skid steer, but no I've never known moles to be that deep.

Moles have several levels of run.

I dont have an answer for a barrier but just something to help with prevention would be planting castor bean plants close to your patio. Nice looking plants and also repel moles, the beans are poisonous though.

Use insecticide on the yard to kill the grubs and the moles should move on.

A mole's primary food source is earthworms, not grubs, so there's that.
An option is to bury hardware cloth at the border, like an underground fence, as deep as you'd like. Twelve to eighteen inches if possible. When snipping the wire, I'd leave the bottom edge raw and flared, just out of spite.

Thats what the "Grass green chemical companies" want you to believe. Moles eat earthworms -God's- so aerating machines.

What Warrior said is true, they can run Deep when they want to. Traps are your best choice.

Not trying to start an argument here but I don't use a lawn service. But I have fought many a battles with moles. I do work for a large Agri Service company and deal with a lot of insects ! I have a large yard with soybeans on one side corn on another and a hay field. I use insecticide every spring and get along good at keeping the moles away. I usually just do one treatment a year and do one strip 2x rate along the hay field. Corn and soybean fields are rotated every other year. Also in my experience if you are using the poison worms that kill moles that you put in the runs make sure you wear gloves to cover your sent. Just my 2 cents good luck and I hope you get them all.

Some good info. Thanks

Not a bad idea. I wonder what the best trick is to get the trench dug for the hardware cloth... A pointed shovel I suppose.