« Back

Dryocosmus kuriphilus

Chestnut gall wasp

Description

2.5 mm. A tiny cynipid wasp, dark brown or black colour with yellow-orange legs. One of the most harmful insects to chestnut in Europe, Asia and Nord America. Females lay up to 100 eggs in several buds from June to August. Hatched larvae overwinter until the following spring, when they prompt the development of rounded galls causing loud deformations on leaves/flowers and twig dieback. Adults emerge finally from the galls through a little circular hole. The main damage is the reduction of shoot elongation and fruit production. Univoltine. It can cause damages in orchards, nurseries, chestnut plantations and sparse chestnut trees in mixed broadleaved forests, from sea level to 1,000 m.

Symptom

Rounded galls causing loud deformations on leaves/flowers and twig dieback. They are green, red brown at the end of the season and during the winter.

Tree Species: Chestnut

Part of a plant- attacked: Leaf / Needle

Pest significance: Harmful

Pest Category: Insects

Invasive Species: Yes

Present in EU: Yes