台大實驗林內茅埔營林區杉木(Cunninghamia lanceolata)林之小蠹蟲種類調查（鞘翅目：象鼻蟲科：小蠹蟲亞科）

Abstract

China-fir (Cunninghamia lanceolata) is an economically important conifer which is mainly used as construction lumber. Scolytids are key forestry pests and some species are also listed as quarantine pests. In 2002, they were the most likely cause for the dying of China-fir trees in central Taiwan. Scolytids are attracted by the volatile chemicals released from trees or wood. Thus in this study we used 12-unit Lindgren multiple funnel traps baited with α-pinene and 95% ethanol to investigate the scolytid species in the China-fir plantation. The trapping took place from June 2004 to May 2005 in the Nei-Mou-Pu Tract of the NTU Experimental Forest. A total of 25 traps were set, and the results showed that 40,366 scolytids belonging to 72 species, 30 genera, and 9 tribes were collected. These 72 scolytid species included 2 endemic species, 44 recorded species, 5 near species and 21 possibly new species (9 species had only one specimen each) in Taiwan. The number of Hypothenemus eruditus (Westwood), Xyleborus affinis (Eichhoff), Phloeosinus pertuberculatus (Eggers), Xylosandrus mancus (Blandford) and Scolytoplatypus pubescens (Hagedorn) amounted to 37, 24.4, 7.8, 7.6 and 6.4%, respectively. They were the top five species of attracted scolytids in the collection. Three 1.5-meter lengths of dead wood were collected in each lot, and each wood was cut into 3 pieces to breed and collect the insects in these woods. This experiment was repeated three times for comparison with the scolytids in the traps. P. pertuberculatus was the third most plentiful species trapped, but it was the most abundant species (46.2% of all scolytid beetles) found in the 9 pieces of wood of the experiment. This investigation provides the fundamental data on scolytids in Taiwan, and how to protect against scolytids in China-fir plantations in the future.