Pissodes weevil-Pissodes piniphilus
From Bugwoodwiki
From: Kolk A., Starzyk J. R., 1996: The Atlas of Forest Insect Pests (Atlas skodliwych owadów lesnych) - Multico Warszawa, 705 pages. Original publication in Polish. English translation provided by Dr. Lidia Sukovata and others under agreement with The Polish Forest Research Institute.
Occurrence: The central and northern Europe, the eastern Siberia.
Host plants: The Scots pine, sporadically the eastern white pine.
Morphology: Beetles are 4-5 mm long, elongated, reddish brown. Elytrae are with large yellowish spot behind the middle on each side. Pronotum is with four white spots. The larva is legless, white, 9 mm long. The pupa looks like P. pini.
Biology: Adults overwinter in litter or in galleries, while larvae only in galleries. Adults fly and oviposit in the period from the second half of April through August. During this time adults have maturation and regenerative feedings. Females lay 1-5 eggs in prepared small holes in the thin bark. Larvae feed within the inner bark and outer sapwood, making banded galleries up to 15 cm long and 4 mm wide. Elliptic pupal chambers filled with white shredded wood are constructed in the wood or between the wood and bark. They are up 10 mm long. Adults emerge through holes of about 2 mm in diameter. The lifespan of adults reaches 2 years.
Damage: P. piniphilus is one of the most serious secondary pests of pine. It infests the upper part of trees, causes resin oozing, fading and dying of shoots and later the death of trees. Adults often transmit pathogenic fungi (causing the pine blister) to the crown during feeding. It prefers 30-50 year old stands, but can attacks 5 up to 100 year old trees.
Preventive measures: Removal of weakened, dying trees, post harvested top and branches.
Control: Removal of infested trees from May through September. The use of trap trees is recommended. The first time they should be exposed in mid-April, and the second time - in mid-June. In stands with the high rate of infestation the trap trees should be exposed the third time in mid-July. Trap trees should be debarked before pupation, that is approx. 6 weeks after exposure. This species prefers shaded parts of trap trees or logs, where they have a contact with soil. Debarked wood should be examined carefully, and if pupating larvae or pupae are found in the wood, they should be sprayed with a contact insecticide. Another type of the trap are logs of about 4 m in length with thin bark. There should be one group of 4-5 pieces per ha. In stands infested by P. piniphilus, trees with the pine blister should be removed first of all, as this species can spread the infection to other healthy trees.
 Photo by Robert Dzwonkowski, , Bugwood.org |  Photo by Stanislaw Kinelski, , Bugwood.org |
 Photo by Stanislaw Kinelski, , Bugwood.org |  Photo by Stanislaw Kinelski, , Bugwood.org |
 Photo by Stanislaw Kinelski, , Bugwood.org |  Photo by Stanislaw Kinelski, , Bugwood.org |
 Photo by Stanislaw Kinelski, , Bugwood.org |  Photo by Stanislaw Kinelski, , Bugwood.org |
