The chemical that is in the Bayer products, and has the "trade name" Merit, is Imidacloprid. It needs to be ingested by the grub, or borer, in this case, in order to kill him, and is systemic, which means it's taken up by the plant roots( and to some extent, through the leaves), so when the bug bites the plant, the bud bites the dust! Some don't like chemicals, and use nematodes, but so far, I've had good luck with the Merit....Arlyn
