Black fir sawyer (Monochamus urussovi)

Kolk A. and Starzyk J. R. 1996.The Atlas of Forest Insect Pests. The Polish Forest Research Institute. Multico Warszawa. 705 pp.

Occurrence

The north-eastern Europe, Siberia, Mongolia, the north-eastern China, Korea and Japan.

Host plants

The fir, larch, pines, spruce, occasionally the birch; in Poland, only the Norway spruce.

Morphology

Beetles are 15-37 mm long, black. This species is similar to M. sartor, but differs with dense yellowish hair on the tip of elytrae. Antennae of males are 1.5-2 times longer than the body, and those of females are slightly longer than the body. The egg is elongated, white, 3.8-5.5 mm long. The larva is legless, about 60 mm long. The pupa is 30-35 mm long.

Biology

Adults fly from late-May through September with the culmination in July. Adults have maturation feeding on young shoots and branches of spruce, fir and other conifers. After mating, females lay 14-40 eggs in holes made with mandibles in the bark and reaching the phloem of stems. One up to 3 eggs are laid in one hole. Larvae feed first under the bark and only slightly in outer sapwood. After overwintering, larvae bore 8 up to 15 cm into the wood. The larva molts 5 times during its development. At the end of galleries in the wood, larvae construct pupal chambers of 4.5-8 cm in length and 16-30 mm in width. Pupation occurs after the second overwintering, usually in late-May or June. Adults emerge 4-5 weeks later through holes of 6-13 mm in width. They live 2 months. This species usually has one generation per 2 years, but occasionally it can have one generation per one or three years.

Damage

M. urussovi is a very serious physiological and technical pest. It occurs in stands damaged by fire or defoliators. It lowers the value of timber. Maturation feeding of adults may be also important.

Preventive measures and control

Similar to M. sartor.