Japanese beetles, a distinctive-looking, green, almost iridescent beetle, attack plants from the time they're larvae in the ground, feeding on roots, until they're adults, eating plant foliage. Pyrethrum, a "natural" insecticide made from chrysanthemum flowers, is a good defense against Japanese beetles, who hate the stuff. You have to wonder if planting chrysanthemums throughout your garden would not only add some color but also act as a natural defense against the beetles? It's worth trying!