Eucalyptus psyllid

Taxonomic classification: Cardiaspina albitextura belongs to the order Hemiptera and the family Psyllidae (jumping plant lice). Originally native to Australia, this insect has become a significant invasive pest in various regions worldwide where Eucalyptus species are cultivated for forestry, ornamental purposes, or oil production.

Host plants: The primary host range is restricted to species within the genus Eucalyptus. The pest exhibits a strong preference for certain species such as Eucalyptus viminalis and Eucalyptus globulus. It can cause devastating impact on both plantation forestry and urban landscape trees by severely weakening them over multiple growing seasons.

Biology and lifecycle: The lifecycle encompasses egg, five nymphal instars, and the adult stage. The most distinct biological feature is the creation of a 'lerp' — a protective covering made of secreted wax and honeydew. The nymphs reside and feed underneath these white, sugary, basket-like structures, which provide significant protection against desiccation and natural predators throughout their development.

Damage and severity: The feeding activity of nymphs causes significant physiological stress to the tree. The initial signs of infestation include chlorotic spots on the leaves at the feeding sites, which soon turn necrotic. Heavy infestations lead to extensive defoliation, stunted terminal growth, and branch dieback. Severely stressed trees become highly susceptible to secondary pests and fungal infections, often resulting in mortality.

Protection measures: Management of the eucalyptus psyllid requires an integrated pest management (IPM) approach:

• Biological control: Introducing or encouraging native parasitoid wasps, which are known to be the most effective regulators of Cardiaspina populations.
• Silvicultural practices: Selecting less susceptible Eucalyptus genotypes and maintaining optimal tree vigor through appropriate site selection.
• Chemical control: Primarily used in nurseries or high-value urban areas, employing systemic insecticides to target nymphs protected by their lerps.