Predatory nematodes commercially packaged are a very safe biological insecticide containing inert material and millions of the beneficial nematodes. Unlike the harmful rootknot nematodes which attack plants, beneficial or predatory nematodes only attack soil-dwelling insects. Nematodes are microscopic, non-segmented eel-like worms one-tenth to one-hundred-twenty-fifth of an inch in length. It is a natural product that will control a broad spectrum of soil dwelling grubs and larvae of pest insects. These naturally occurring organisms, sold by a number of different companies, are applied to the soil, then seek out and move to the target insects to kill them. Predatory nematodes will attack all the larvae and grubs found in the soil. These will usually be from the eggs of beetles and weevils. For more details see the file "Tips On Using Predatory Nematodes".