The Olive Lace Bug (Froggattia olivina) is an Australian native sap-sucking insect posing significant threats to olive groves. It specifically targets olive trees (Olea europaea), potentially reducing yields and causing tree death if left unmanaged. Olive lace bug infestation is considered a serious threat to the olive industry in Queensland, New South Wales, Victoria and across Australia.

Olive Lace Bug (Froggattia olivina) infestation on the underside of an olive leaf, showing multiple life stages 

nymphs, adults, and characteristic black excrement spots.

STAGES OF OLIVE LACE BUG 

Lifecycle

Female Olive Lace Bugs insert eggs into the tissue on the undersides of leaves, usually along the midribs. Eggs hatch into nymphs, which pass through five moults before reaching adulthood. Olive Lace Bug overwinters as eggs, with hatching typically occurring in early spring (September to October). Adults may also overwinter in protected locations on trees. Depending on climate conditions, there may be one to four generations per year, with a lifecycle ranging from 12-23 days in warm weather to up to 7 weeks in cooler conditions.

Distribution and Spread

Originally native to New South Wales and southern Queensland, olive lace bugs have spread throughout Australia, excluding the Northern Territory. The movement of olive plants and industry activities have facilitated this spread. Juvenile bugs, relatively immobile, cluster on leaf undersides and are easily spread through planting materials, workers, and tools. Adults disperse via short flights or wind

Identification and Monitoring

• Regularly inspect leaf undersides from early spring. 
• Early infestations appear as rusty-yellow spots about half the size of a pin-head on the upper surface of leaves, contrasting clearly with the dark green leaf surface. 
• Severe infestations result in leaf browning, premature drop, and twig dieback.

Damage and Symptoms

Heavy infestations significantly affect tree vigor, delaying flowering and fruiting, reducing yields for up to two seasons, and potentially causing young tree death. Mature trees can also be severely affected, with death observed in extreme cases.

Host Plants

Known hosts include native mock olive (Notelaea longifolia) and cultivated olives (Olea europaea).

Integrated Pest Management (IPM) Strategies

• Regular Monitoring: Check frequently to detect early infestations. 
• Cultural Practices: Keep trees healthy through adequate fertilisation, irrigation, systematic pruning, and canopy management. Avoid stress caused by poor soil preparation, proximity to large eucalypts, or nutrient deficiencies.
• Biological Control: Support beneficial predators such as lacewing larvae, ladybird beetles, and predatory mites. Note: Biological controls require a continual supply of the pest to be effective, which can be difficult to achieve in the long term.
• Spray Controls: Apply proven products known to be effective in the control of OLB.  See more:  Olive Lace Bug Products

Effective Spray Regime

• Spray soon after initial detection. Severe infestations may require a second treatment 10-14 days later. 
• Apply thorough coverage on leaf undersides. 
• Prune regularly to open the canopy, improving spray effectiveness and reducing pest habitat.

Long-term Sustainability

• Maintain optimal tree health with regular nutrient checks and soil testing. 
• Remove dead or unwanted branches. 
• Educate staff on proper pest identification and management techniques.

By proactively managing olive lace bug, you safeguard the health and productivity of your olive groves, ensuring sustained profitability.