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FS ShieldForest Health Protection, Southern Region


Dendroctonus terebrans (Olivier)

Importance. - The black turpentine beetle is found from New Hampshire south to Florida and from West Virginia to east Texas. Attacks have been observed on all pines native to the South. This beetle is most serious in pine naval stores, pines stressed for lightwood production, and damaged pines in urban areas.

Identifying the Insect. - The adult insect is dark brown to black in color and 3/8 inch (10 mm) in length. The posterior end is rounded. Full grown larvae are white with a reddish brown head and about 1/3 inch (8 mm) long. Pupae are about 1/4 inch (6 mm) in length and yellowish white.

Large pitch tube

Large pitch tube.
(Click for detail. JPG 52K)
Larvae feeding and excavation - note frass

Larvae feeding and excavation -
note frass. (Click for detail. JPG 53K)

Identifying the Injury. - Black turpentine beetles attack fresh stumps and the lower trunk of living pines. Initial attacks are generally within 2 feet (60 mm) of the ground. Attacks are identified by white to reddish-brown pitch tubes about the size of a half dollar. The pitch tubes are located in bark crevices on the lower tree bole, usually below a height of 10 feet (3 m). Infested pines are often attacked by other bark beetles.

Biology. - Adult beetles bore into the cambium and construct galleries which usually extend downward. Eggs are laid in clusters and hatch in 10 to 14 days. Larvae feed side by side, excavating a large continuous area. The life cycle takes from 2 1/2 to 4 months, depending on the season. There are two to four generations a year.

Control. - Natural enemies and good tree vigor generally keep black turpentine beetle populations at low levels. Newly attacked trees can often be saved by spraying the base to the highest pitch tube on the trunk with an approved insecticide. Preventive sprays are also effective for high value trees. The prompt removal of infested trees also helps to control outbreaks. Forest management practices which promote tree vigor and minimize root and trunk damage help prevent infestations.