European woodwasp (Sirex noctilio)
Kolk A. and Starzyk J. R. 1996.The Atlas of Forest Insect Pests. The Polish Forest Research Institute. Multico Warszawa. 705 pp.
Europe, Siberia and Mongolia, introduced to the New Zealand and Australia.
Mainly the Scots pine, rarely other conifers.
Males are 10-30 mm and females are 17-32 mm long. Antennae are black. Sexual dimorphism is clear. Females are black with bluish shine. Ovipositor is 1.5 times shorter than forewing. The head and thorax of males are black with blue shine. Abdomen is reddish with the black first and second segments, eighth tergit, and two last sternits. The egg is oval, 1 mm long. The larva is cylindrical, up to 20 mm long, whitish, with the spine on the end of abdomen. The pupa looks like Sirex juvencus.
Adults fly from July to August at the day temperatures higher than 12oC. Mating occurs on breeding material. The female oviposits singly into the tunnel made with the ovipositor in the sapwood. Larvae hatch 10-20 days later and bore long galleries into the wood packing them behind themselves with mixed frass and white shredded wood. Pupal chambers are constructed under the angle of 45 degree to the stem surface. Larvae overwinter twice and pupation occurs in May. This species has one generation per 2 years.
It is a serious technical pest occurring mainly in weakened stands.
Preventive measures and control
Similar to U. gigas.