Fruit Tree Leafroller

Archips argyrospila

1. Identification

• Common name: Fruit-tree leafroller
• Scientific name: Archips argyrospila Walker
• Order: Lepidoptera
• Family: Tortricidae

2. Pest description

• Adults: Moths of 18–22 mm wingspan; forewings orange-brown with darker irregular patterns; hindwings brownish.
• Larvae: Yellowish-green to brownish-green, brown head; they roll leaves with silk threads, feeding inside.
• Pupae: Formed inside the rolled leaves.
• Eggs: Laid in flattened masses on the bark of branches, usually covered by a protective layer.

3. Main hosts

• Pome fruits: apple, pear.
• Stone fruits: plum, peach, cherry.
• Other broadleaf and ornamental plants may be attacked.

4. Symptoms and damage

• Leaves rolled and bound together by silk threads, containing caterpillars inside.
• Partial defoliation, especially on young shoots.
• Damage to flower buds and flowers, reducing fruit set.
• Superficial perforations on young fruits, which may cause deformations.
• In severe attacks, reduction of vigour and production.

5. Biological cycle

• One annual generation in temperate climates; two in warmer regions.
• Eggs overwinter; hatching in spring, coinciding with budbreak.
• Caterpillars feed for 3–5 weeks, passing through 5 instars.
• Pupation in the rolled leaves; adults emerge in late spring or summer.
• Development favoured by mild springs and an abundance of young shoots.

6. Monitoring

• Observation of rolled leaves containing caterpillars.
• Inspection of flower buds and young shoots in spring.
• Pheromone traps for detection of adults and forecasting of flight peaks.
• Assessment of the degree of defoliation and damage to floral organs.

7. Management measures

• Cultural: Removal of rolled leaves with caterpillars; pruning of heavily infested branches; elimination of local foci; maintenance of vigorous trees.
• Biological: Use of authorised entomopathogenic microorganisms; application of microbial bioinsecticides; conservation of natural enemies through appropriate cultural practices.
• Integrated protection: Regular monitoring; intervention only when necessary; practices that reduce the survival of young caterpillars and the formation of rolled leaves.

Bibliographic references

• EPPO Global Database – Archips argyrospila
• CABI Invasive Species Compendium – Archips argyrospila
• Chapman, P. J. & Lienk, S. E. (1971). Tortricid Fauna of Apple in New York. New York State Agricultural Experiment Station.
• Powell, J. A. (1980). Tortricidae (Lepidoptera) of North America. University of California Press.
• Alford, D. V. (2007). Pest and Disease Management Handbook. Blackwell Publishing.