Common pine shoot beetle (Tomicus piniperda)
Kolk A. and Starzyk J. R. 1996.The Atlas of Forest Insect Pests. The Polish Forest Research Institute. Multico Warszawa. 705 pp.
Europe, the northern Asia, Japan, Algeria and the Canary Islands.
The Scots pine and other pine species, sporadically the spruce, larch and fir.
Adults are 3.0 - 5.0 mm long, shiny, black with reddish-brown elytrae. Elytral declivity is with grooves, which are not present in T. minor. Margins of declivity are with small sharp teeth.
Adults overwinter in the thick bark of the basal part of pine trees where they enter in October-November after maturation feeding. At times they overwinter in shoots. Overwintering adults initiate flight on the first warm days (10-12oC) of spring which occur in mid-March or early-April. Females colonize either recently cut pine stumps, logs, or, at times, infest the trunks of weakened trees with a thick bark. After mating, females construct individual vertical egg galleries within the inner bark and outer sapwood. Egg galleries extend 8 - 20 cm in length. On standing trees egg galleries are usually straight, while on fallen trees they are pipe-shaped that helps the male to clean a gallery out of shredded bark. Females lay eggs singly in niches that are cut into both sides of the egg gallery. Total number of eggs laid by a female is about 100. After hatching, larvae construct feeding galleries, which first are perpendicular to egg gallery, then irregularly. Larvae pupate in the bark. The newly formed adults initiate flying July. They fly to the crowns for maturation feeding primarily inside lateral shoots, mostly in the upper half of the crown. Maturation feeding lasts until October. Old adults, after laying eggs, fly to the crowns to have regenerative feeding, which lasts 6 weeks. Then, in late-May and June, a portion of them may start to lay eggs of so-called sister generation.
T. piniperda is one the most serious secondary pests of pine. It infests standing or laying trees, mainly the lower part with the thick bark. Attacked trees are usually possible to recognize by pitch tubes. The most severe damage caused by T. piniperda is the destruction of shoots during maturation feeding. When shoot feeding is severe, tree height and diameter growth are reduced. The tree crowns have a specific shape. It can often be observed in the stands close to timber yards.
Removal from the forest all potential unbarked material suitable for infestation such as: timber, weakened trees, windthrows etc., in the period from October through March.
There are several possible control methods:
- the use of trap trees in the period from December through February only in stands with high infestation risk due to Tomicus spp. (max. 5 per ha). Traps should be debarked before pupation, that is when maternal galleries are about 10 cm long (usually from 5th to 25th May in Poland).
- searching for, cutting and removing all infested trees with adults from a woodland in the period from April through June;
- the use of pheromone traps or trap trees baited with attractants;
- debarking of infested trees and traps from April through September. Debarking is not required, if trap trees will be removed from a woodland and/or utilized during 2-3 weeks after flight initiation.