Distribution and attack behaviour of the red turpentine beetle, Dendroctonus valens, recently introduced to China

The red turpentine beetle, Dendroctonus valens LeConte (Coleoptera: Scolytidae), was found for the first time in China in Yangcheng and Xinshui counties, Shanxi province in 1998, and in Hebei province in 1999. The beetle mostly attacks the oil pine Pinus tabulaeformis Carriére. By 2003 the beetle was found in 85 counties of three provinces in north China and the area of infested pine forests covered more than 700,000 ha. The elevation above sea level of forests infested is more than 800 m. The beetles most frequently attack trees on hilltops and at the forest edge, fewer attacks occur in the centre of the stand. This correlates with the damage done to the trees by wind or man. Weak and dying trees are more vulnerable to attack than healthy ones. The most attractive breeding sites are fresh stumps. The population density of the beetles is higher in the forests on northern slopes than on southern slopes. Most of the bores in the trunk are less than 0.5 m above ground; the galleries are found also on roots.