Two Agricultural Research laboratories are investigating biological control methods for beet armyworms. One is the Spodoptera exigua nuclear polyhedrosis virus, which damages the armyworms but is safe for humans, animals and other beneficial predators. Another is the Cotesia marginventris, a wasp which lays eggs on the pests even when the latter is hiding under the leaves. The eggs hatch into larvae that feed on the nutritious catterpillar.
Beneficial insects are often victims of "friendly ...