Giant willow aphid

The giant willow aphid (Tuberolachnus salignus) is a prominent member of the Aphididae family, distinguished by its large size and a dark dorsal tubercle. It is one of the most visible aphid species found on willow trees, often clustering in dense masses on the bark of stems and branches.

This pest exclusively targets woody plants, primarily members of the Salix genus, including weeping willow and goat willow, and occasionally the Populus genus. Because they feed on the thicker bark rather than the leaves, their presence can often go unnoticed until a significant infestation has occurred.

The life cycle involves rapid asexual reproduction throughout the spring and summer months, allowing the population to reach extremely high levels in a short time. Sexual reproduction occurs in the late autumn, leading to the deposition of overwintering eggs, which are typically laid in crevices on the tree bark to survive the winter season.

The damage caused by this aphid is significant, as thousands of individuals drain the plant's sap, leading to tree stress and weakening. The production of large amounts of honeydew promotes the growth of sooty mold, which coats the bark and leaves, hindering photosynthesis and causing further decline in the tree's overall health and aesthetic value.

Effective management requires a combination of monitoring and integrated pest control strategies. Chemical intervention should be timed with the peak of the infestation.

• Application of systemic insecticides for severe outbreaks.
• Promoting natural predators like ladybirds, lacewings, and hoverflies.
• Regular inspection of bark for egg clusters during the dormant season.
• Maintaining tree vigor through proper hydration and soil nutrition.