Calleta silkmoth

Callosamia calleta is a member of the Saturniidae family, order Lepidoptera. It is a large nocturnal moth native primarily to regions of North and Central America. Although often viewed by entomologists as a collector's item, in an agronomic context, the larval stage of this insect can pose a threat to various deciduous woody crops.

The caterpillars of this species are characterized by polyphagy within woody and shrub vegetation. They damage crops such as ash, privet, laurel, and various ornamental shrubs. In intensive orchard or nursery conditions, a massive emergence of larvae can lead to significant defoliation, thereby weakening the trees.

The biology of the pest involves a complete metamorphosis: egg, larva (caterpillar), pupa, and adult. The female lays eggs on the underside of the leaves of host plants. Upon hatching, the caterpillars go through five instars, feeding actively on plant tissues. The insect overwinters in the pupal stage inside a tough, silk cocoon, which is firmly attached to the branches of the host plant for protection against harsh conditions.

Damage patterns manifest as skeletonization or complete consumption of the leaf blades by late-instar caterpillars. The economic damage is reflected in reduced photosynthetic capacity, which negatively impacts biomass accumulation. Young trees that have been attacked may lose their vigor, becoming susceptible to secondary pests and fungal infections.

Protection strategies include a multifaceted approach:

• Manual removal of cocoons during the autumn-winter period, which significantly reduces the population of the next generation.
• Monitoring of plantings during the period of peak moth activity and oviposition.
• Application of biological preparations based on Bacillus thuringiensis bacteria when early-instar caterpillars are detected.
• Use of systemic insecticides in nurseries where infestations reach threatening levels.