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Pachynematus montanus

Spruce sawfly

Description

A species of the sawfly family, 6-8 mm long. The females lay single eggs on budding needles in the May. The larvae, hatched after about 7-12 days, begin to consume fresh needles first. Later also older needles are damaeged. As a single larva may consume as many as 100 needles, upper canopy defoliation may occur. In late summer the larvae descend to the ground to pupate in the litter and eclose in spring. Repeated damages inhibits the tree growth rate and causes dieback of upper branches. The effects are similar to those caused by the small spruce sawfly. The latter, however, inhabits higher altitudes of 600-900 m a.s.l. and attacks more typically older or mid-aged stands. 

Symptom

Damaged tree tops.

Tree Species: Spruce

Part of a plant- attacked: Leaf / Needle

Pest significance: Harmful

Pest Category: Insects

Invasive Species: No

Present in EU: Yes

Last observations

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

Pachynematus montanus Spruce sawfly
ak73
Number of votes: 0
Published: 29.8.2022

Pachynematus montanus Spruce sawfly
ak73
Number of votes: 0
Published: 29.8.2022

Pachynematus montanus Spruce sawfly
ak73
Number of votes: 0
Published: 29.8.2022

Pachynematus montanus Spruce sawfly
ak73
Number of votes: 0
Published: 29.8.2022