Three ambrosia beetle species, Xyleborus glabratus, Monarthrum mali, and Euwallacea fornicatus belong to subfamily, Scolytinae, showing similar morphology and body size, but their flight capability and patterns showed species-specific. Body length of Xyleborus glabratus and Monarthrum mali was negatively correlated with flight capabilities; shorter beetles performed longer average flights, longer single flights, total flight distance, and total flight time. Elytral length also was negatively correlated with flight distance in X. glabratus and M. mali. Conversely, only average flight time of E. fornicatus was positively correlated with body length, pronotal width, and elytral length. Body length had no effect on the flight velocity of any of the three beetle species examined. Therefore, our results indicate that body size characteristics of ambrosia beetles differentially influence on their dispersal by species.

Thermal death kinetics was examined to develop a heat treatment method to control the Alnus ambrosia beetle, Xylosandrus germanus, in wood packing materials for export goods. To determine the feasibility of microwave irradiation as an alternative treatment, we performed laboratory experiments on the blocks (200x200x250mm) of Douglas-fir artificially infested with live adults with subsequent 2.45GHz microwave energy irradiation. The 100% mortality of treated Alnus Ambrosia Beetle was achieved above 58℃ of the measured wood temperature, regardless of irradiated time. All measurement points in the blocks reached 58℃ within 84-312 seconds with microwave irradiation by wood weight. Likewise, the 100% mortality of breetles were observed by hot water treatment on 52℃. We need further experimental verification, but commercial microwave (2.45GHz) treatment is a feasible alternative to conventional heat treatment to control Alnus ambrosia beetle on the wood packing materials for export goods.

An ambrosia beetle, Platypus koryoensis, is a vector of Raffaelea quercimongolicae that is known to cause Korean Oak Wilt (KOW), one of the serious threats to forest healthy in Korea. To manage P. koryoensis properly, it is necessary to clarify flight period of the adult. This experiment was conducted to elucidate the relationship between temperature and the flight period based on field observation in three forests consisted of Quercus mongolica from 2007 to 2009 except winter season. Date of flight period for 50% (FP50) was estimated by the cumulative Weibull distribution model based on cumulative proportion of the adult density and air temperature. Relationship between site temperature and the date of FP50 of P. koryoensis was the most significant when temperatures below 6.5℃ were excluded, suggesting lower threshold temperature for the flight period based on the site temperature. The pooling cumulative proportion of flight period against degree days was well described by the degree-day model, which has explanatory power for the 89% of year and site variation in the flight period and predicted accurately the flight pattern in 2011.

Spatio-temporal distribution pattern of an ambrosia beetle, Platypus koryoensis (Murayama) which is vector of Raffaeleaquerci-mongolicae K.H. Kim et al, a causative agent for Korean oak wilt (KOW) was examined in the stand level. Spatial distribution of P. koryoensiswas influenced by their density. Relationship between degree of aggregation and density was positively correlated when the density was extremely low or high whereas the relationship was reverse when the density was intermediate. Patch of P. koryoensis formed around or near dead trees or partial dead trees, suggesting these trees indicated epicenter of P. koryoensis. Fraction of trees attacked by less than 100 individual of P. koryoensis in the stand per year increased abruptly whereas fraction of trees attacked over 1,000 individuals of P. koryoensis increased gradually. Our results showed that the dead trees would be an epicenter of P. koryoensis and the number of trees killed by the ambrosia beetle would be reduced by lowering total population of the ambrosia beetle around the epicenter.

In this study, we examined the spatial dependence and association of Ambrosia beetle, Platypus koryoensis, which is the vector of oak wilt disease caused by Rafaelea sp. using two geostatistical methods. Two adjacent sampling plots were selected and named as "Sector A" and "Sector B". Sector A area was 63 ha and Sector B area was 420 ha, respectively. We arbitrarily separated each sampling plot by 50m×50m grids. Sector A and B were separated by 19×15 and 43×41 grids, respectively. The oak wilt disease damage level of tree was classified by amount of frass of Ambrosia beetle near target oak tree as follows: Lost tree (LT), Severe damage (SD), Intermediate damage (ID), and Light damage (LD). Number of each damage level of oak tree was counted and recorded in each sampling grid. Spatial dependence and association of oak wilt damage was analyzed and compared using mathematical variogram models and spatial analysis by distance indices (SADIE). Variogram model ranges were 179~368m in Sector A and 634~1073m in Sector B, respectively. The damage levels of all trees in each sector were indicated as aggregated distribution by aggregation indices of SADIE (Ia > 1). Each damage level pair had strong association in the consecutive orders than in any random order based on the results of SADIE association test. The spatial dependence and association of oak wilt damage levels presented here provide the baseline information necessary to understand and manage oak wilt disease in Korea.