Abstract:

Dendroctonus valens LeConte is a new recorded species in China. It is devastating and highly dangerous to the stands of Pinus tabulaeformis, and it can cause the ten year old trees to die in a short time. The pest overwinters mainly as adult or mature larvae (77.5%), others as 2 to 3 instar larvae (21.7%), and a few as pupa (0.8%). When the population density is low, the pest mainly harms the weak firedtrees, newfelled trees, and the new stumps. When the population density is high, the pest can quickly attack the healthy trees with breast height diameter over 10cm and over 20 years old. The damaging situation in low canopy density forests is higher than that in the high canopy density forests.

Key words: Dendroctonus valens LeConte, Morphological characters, Bionomics