Milky Spore Granular - 20 lb bags/Pallet of 42Combine Milky Spore With Beneficial Nematodes To Maximize Japanese Beetle Grub Control! Milky Spore contains spores of the bacteria Paenibacillus popilliae (formerly Bacillus popillae), which work specifically against the grub stage of the Japanese beetle (Popilia japonica). It poses no threat to people, animals, plants or beneficial insects. When Milky Spore is introduced into the soil, it will lie dormant until grubs begin feeding on roots where the