Willow Puss Moth

The Willow Puss Moth (lat. Cerura multiscripta) is a moth species belonging to the order Lepidoptera and the family Notodontidae. As an agricultural and forestry pest, it primarily targets trees of the Salicaceae family, specifically willows and poplars, often causing localized defoliation in nurseries and urban landscape areas.

The host range of Cerura multiscripta is centered on species of Salix and Populus. The larvae are voracious feeders, typically found on the foliage during the summer months. Given their biology, they can significantly impact the aesthetic value of ornamental willow trees and the biomass production in fast-growing poplar plantations.

The life cycle involves complete metamorphosis. The adults are nocturnal moths, while the larvae display characteristic defensive behaviors when threatened. The pupal stage is passed within a tough, camouflage-colored cocoon, which the moth constructs on tree trunks or branches. This protective casing makes the insect resistant to harsh environmental conditions during the winter diapause.

Damage is characterized by the consumption of leaf tissue. Early instar larvae skeletonize leaves, while late instar larvae consume the entire leaf blade, leaving only the central veins. Heavy infestations lead to extensive defoliation, causing physiological stress to the tree, which can result in stunted growth and increased susceptibility to secondary fungal infections or climatic stress.

Integrated Pest Management (IPM) strategies for the Willow Puss Moth include:

• Monitoring foliage for early signs of skeletonization and the presence of eggs.
• Manual removal of cocoons during the winter dormant season to reduce the next spring's population.
• Application of selective biological insecticides, such as Btk (Bacillus thuringiensis kurstaki), which specifically target moth larvae without harming beneficial insects.
• Encouraging natural biological control agents, including parasitic wasps and predatory birds that feed on moth larvae.