Spotted tussock moth

Systematic position. The spotted tussock moth (Lophocampa maculata) is a moth species belonging to the order Lepidoptera, family Erebidae, and subfamily Arctiinae. It is a well-known forest insect native to North America, recognized for the distinctive appearance of its larvae.

Host plants. This species is a polyphagous pest, meaning it feeds on a wide range of host plants. It primarily targets deciduous trees, including maple, birch, alder, poplar, willow, and oak. It is also frequently found in orchards, where it can feed on various fruit-bearing trees, potentially impacting tree health and fruit production.

Biology and life cycle. The species undergoes a complete metamorphosis, consisting of egg, larval, pupal, and adult stages. The winter is typically spent in the pupal stage, encased in a silken cocoon hidden within leaf litter or bark crevices. Adult moths emerge in early summer, mate, and deposit egg clusters on the underside of host leaves. Larvae emerge and feed gregariously during their early stages before dispersing.

Nature of damage and pest impact. The larvae are the stage responsible for damage. They consume leaf tissue, often causing skeletonization of leaves, and in cases of severe infestation, they can defoliate entire branches or trees. The cumulative stress caused by repeated defoliation can stunt growth, reduce the tree's vigor, and increase susceptibility to secondary pathogens and environmental stressors.

• Conduct regular visual inspections to identify egg masses and early larval colonies.
• Physically remove and destroy infested leaf clusters where larvae are concentrated.
• Utilize biological control agents, such as formulations of Bacillus thuringiensis.
• Apply targeted insecticides when pest populations exceed defined economic thresholds.
• Conserve local populations of predatory wasps and birds that naturally keep larval numbers in check.