Severe defoliation disrupts the natural cycle of nutrients. It also increases the temperature and amount of sunlight that reaches the forest floor, which can be damaging for shade-adapted wild flowers and other plants. Widespread defoliation can also have negative impacts on wildlife. Defoliation of oak trees decreases acorn production, which is an important food supply for many animals. Many leaf-feeding insects can also starve when gypsy moth strips the forest canopy.
Successful management requires an integrated approach based on a number of techniques.
The BT sprays used for gypsy moth affect only caterpillars, and are completely harmless to all other animals, including bees and other insects, birds, pets, and humans. In regions where gypsy moth has been established for a number of years, natural controls help keep populations in check during most years. Natural enemies include insect parasites that attack egg and caterpillar stages, predators such as birds, and disease organisms. Gypsy moth is especially susceptible to a virus that is often responsible for the crash of high populations. A fungal disease of gypsy moth called Entomophaga maimaiga has recently has been introduced into Ohio and it is a promising tool for gypsy moth management.