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Cephalcia abietis

Spruce webworm

Description

The males occur in late May and June. They are more active than females. After mating the females lay 10–12 eggs in groups in the tree canopy. The eggs are laid on the tree needles in linear or cluster arrangements. The hatched larvae become active, spinning fine silk into a nest to live in. The larval frass normally aggregates inside. The larvae are hairless, light green and 15–18 mm long in maturity. In September they burrow in the ground litter to spend 1–3 years in dormancy and eclose in spring. The pest’s primary targets are aged spruce stands (over 60 years) in highland areas. Infested parts of tree canopy turn rusty brown and the webby pouches with frass are visible from a distance. The spruce webworm is a dangerous pest of spruce monocultures causing serious economic losses to these stands.  

Symptom

The infested parts of the crowns are rusty brown in color and bags with needles and droppings are also visible from a distance.

Tree Species: Spruce

Part of a plant- attacked: Leaf / Needle

Pest significance: Very harmful

Invasive Species: No

Present in EU: Yes

Last observations

There are a total of 2 observations of the species in the system

Cephalcia abietisSpruce webworm
Katarína Bobríková
Number of votes: 0
Published: 26.4.2025