Moles make tunnels underground where they live in order to seek and eat insects, including earthworms and grubs. They have long noses, webbed front feet, no ears, and are are gray to brown and 6-inches long.
You can tell you have moles because you'll have mini mountain ranges and soil volcanoes in the yard.
Castor oil or Mole-Med can be used to repel them. To make your own mix see http://www.greenviewfertilizer.com/articles/voles-moles/
My usual method is to keep a supply of Castor Bean seeds from last summer's crop and wherever I see a tunnel, I drop in a seed.
As a result we have 2-inch tall Castor Bean plants coming up in odd places but they are easy to mow down and the moles are long gone, having relocated to some other yard.
This year I'm going to try the Deadset Mole Trap because the problem is bigger than ever and the company sent me one to see how it works. Here's a link to the video showing how to set it.
Even though this summer is predicted to be as awful as last year with drought and record high temperatures, I bought more Castor Bean seeds to plant. Gardeners are eternally optimistic, aren't you?
I'll let you know how the Sweeney's Deadset trap works.