Connor in Fairfax writes: “I’m having trouble with moles. They used to just be in my backyard, but now they’re making their way to the front. I treated for grubs last summer/fall with milky spore powder. Would it be a good idea to treat my lawn with it again? What is the best way to get rid of moles?”
The milky spore was a good start, Connor. This naturally-occurring soil organism would have wiped out any grubs that were in the turf when you applied it. And it will continue to make that soil grub-unfriendly for decades, eliminating one of the moles’ favorite foods. But it doesn’t affect their other underground food sources, like earthworms and sleeping cicadas.
The next logical step would be to treat the soil with a high concentration of castor oil, preferably a professionally-packaged product, like “Mole Med” from Gardens Alive. The castor oil infuses the soil with a scent that makes moles (and voles) miserable and hopefully drives them away. After that, we’re talking spring-loaded traps, which are large, cumbersome, and can be difficult to set.
But now there’s another option, new just this year: an FDA and organically approved (OMRI listed) treatment called “Mole Zap.” It uses CO2 cartridges to eliminate the bothersome burrowers by displacing the oxygen in their runs. The company behind the product just sent me some samples, and the device looks pretty cool and easy to use