Bacillus thuringiensis subsp. B. t . consists of viable endospores and crystals that must be ingested by the larvae. After the larva feeds, its gut is paralyzed. Then the larva stops feeding and dies. One to three applications may be necessary depending on population levels.
Parasitic nematodes enter the insect's body through openings in the exoskeleton.
The nematodes multiply inside the host insect and release a bacterium that is toxic to the host. The nematodes complete their life cycle within a few days. Large numbers of infective stage nematodes are produced that will search for new hosts. These beneficial nematodes can be applied as a drench to the growing media and to soil under the benches. Adequate soil moisture is needed in order for the nematodes to move within the soil surface.