St. Gabriel Laboratories Milky Spore Review

Milky Spore is a bacterium that infects and kills Japanese Beetle grubs. It is a host specific parasite, so it doesn't harm anything but Japanese Beetle grubs. It controls adult Japanese Beetles, of course, by killing the grubs before they become adults. The initial cost is kind of steep($90 for 100ft by 100ft), but one treatment lasts practically forever, as the infected individual leaves millions of spores behind when it dies. There has been some discussion about whether the spores are cold hardy in northern climes, but the latest data suggest that they are.

This product is my favorite control method for Japanese Beetles, because controlling adults is so hard. Traps are OK, but they attract the beetles, and the chemicals needed to kill an adult are pretty strong stuff. It also has a side benefit if you have a mole problem. It won't eradicate the moles, but moles tend to follow grubs. Moles love grubs, it's like they're little mole Krispy Keme donuts that don't make you fat. If you have a lot of moles it's probably because you have a lot of grubs. When the grubs go away, the moles will generally move on looking for them elsewhere.

There are limitations to this product. The treated areas will not produce adult Japanese Beetles, but there is nothing keeping adults from flying in from other areas. For this reason, it does work better as a community effort. (And the closer you are to the center of that area, the better.) Community in this case isn't like a town or anything, but the more area that gets covered the better the results. At my house, I've gotten my immediate neighbors to let me treat their yards, and my roses have not had an infestation since.