Intermediate Chestnut Tortrix

Cydia fagiglandana

1. Identification

• Common name: Intermediate chestnut tortrix moth
• Scientific name: Cydia fagiglandana Zeller
• Order: Lepidoptera
• Family: Tortricidae

2. Pest description

• Adults: Small moths (≈ 12–16 mm wingspan); greyish-brown forewings with discreet patterns; brownish hindwings.
• Larvae: Pinkish-white to reddish-pink body; brown head; up to 12 mm long.
• Eggs: Laid singly, whitish, deposited on the skin of the fruits or on nearby leaves.

3. Main hosts

• Chestnut tree.
• Oak, especially medium- to large-fruited species.
• In chestnut, it mainly affects intermediate-cycle varieties, coinciding with fruit development during the pest flight period.

4. Symptoms and damage

• Perforations in the bur and in the chestnut shell.
• Internal galleries that destroy the kernel, leading to premature fruit drop.
• Infested fruits show exit holes and internal residues.
• Significant damage in chestnut groves with low monitoring or high pest pressure.

5. Biological cycle

• Winter spent as a mature larva in the soil, in cocoons.
• Adults emerge between May and August, depending on weather conditions.
• Females lay eggs on developing fruits.
• Larvae feed inside the chestnut until they complete their development.
• Exit from the fruit to pupate in the soil.
• One generation per year.

6. Monitoring

• Pheromone traps for detection and monitoring of flights.
• Observation of fruits with early perforations.
• Assessment of premature chestnut drop.
• Historical records of the holding for annual risk forecasting.

7. Management measures

• Cultural: Collection and destruction of fallen fruits; removal of infested fruits; surface tillage of the soil to expose cocoons.
• Biological: Conservation of natural enemies (egg and larva parasitoids).
• Integrated protection: Intervention based on pheromone monitoring; synchronization of treatments with the flight peak; use of selective methods compatible with natural enemies.

Bibliographic references

• EPPO Global Database – Cydia fagiglandana.
• CABI Invasive Species Compendium – Cydia fagiglandana.
• Alford, D. V. (2007). Pest and Disease Management Handbook.
• Branco, M. et al. (2014). Pests of chestnut in Europe.
• Brown, J. W. (2005). World Catalogue of Insects – Tortricidae.