Great spruce bark beetle - Dendroctonus micans Kugel.From: Kolk A., Starzyk J. R., 1996: The Atlas of Forest Insect Pests Occurrence: The central and northern Europe, Siberia and Japan. Host plants: The Norway spruce, rarely Scots pine and larch. Morphology: It is the biggest European bark beetle of 6-9 mm in length. The body is robust, cylindrical, black or dark brown, covered with tiny yellowish hair. Elytrae are with rows of punctures. The declivity is covered with reddish hair. Biology: Adults fly from May through August. After mating, females chew egg galleries under the bark. Egg galleries are up to 10 cm in length, irregular and made in the basal part of the stem. They infest living trees, thus pink-whitish, funnel-shaped pitch tubes are formed around entrance holes. The female lays up to 100 eggs in interconnecting chambers, on one side of the chamber. Young larvae feed in groups on inner bark and phloem packing a mixture of frass and shredded bark behind them. Pupae are found in pupal cells among the larval frass. Emerged adults have maturation feeding near pupal chambers. The overwintering occurs in the imaginal or larval stage. This species usually has one generation per year. Damage: In Poland this beetle is quite rare. Locally it can make damages in 20-40 year old stands, first of all infesting wounded trees or trees damaged by lightning. Preventive measures and control: Avoiding wounds on living trees during harvesting operations. Removal of infested trees, especially those attacked by root fungi or other pests, is recommended.
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Forest Pests: Insects, Diseases & Other Damage Agents |
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