| Anoplophora glabripennis is a serious borer of trees worldwide. In order to find out its new occurrence developments, spreading trends and spreading channels, surveys were carried out in 154 counties, prefectures or cities from 16 provinces, municipalities or autonomous regions from 2000 to 2003. In the occurrence regions, 139 mainly cultivated tree species were tested for insect resistance and resistance mechanism. Determination and analysis of Anoplophora glabripennis control effects were carried out in the 4 control sample plots in North China, Northeast China and Northwest China, and a set of effective control measures were selected.Investigations showed that Anoplophora glabripennis was occurred in the places of Harbin(40° 45'N), Mudanjiang(129° 36' E) and Shigatse(88° 53' E) which widened its occurrence area by 2 degrees in latitude northward, 2 degrees in longitude eastward and 15 degrees in longitude westward compared with that of 20 years ago. New epidemic regions were found out in the cities of Mudanjiang, Daan, Dehui, Panshi, Jilin, Kurle, Linzhi, Lhasa, Shigatse, etc. This is a dangerous signal and indicates that this pest is spreading fast because of its finding in Qinghai-Tibet plateau, Xinjiang Uygur Autonomous region and Heilongjiang province. Therefore, the pest control in these new epidemic regions is important for the protection of the greening achievements in western and Northeast China, The investigation also showed that the rampant occurrence regions of the insect locate in the region south to Jilin-Changchun-Siping-Linhe line, north to Yangtze River, east to Wuwei-Xining line, or between 29° to 44°N and 100° to 127°E.The major environmental factors affecting Anoplophora glabripennis distribution are temperature and humidity. In its distribution regions, the average temperature in January is -18.3℃, and the annual mean temperature is 3.9℃. The average temperature in spring is above 5.8℃, above 2.6℃ for autumn and above -15.6℃ for winter. The average humidity in spring is above 37%, annual average humidity is above 39.4%, and the annual precipitation is above 130.4mm. The above figures show that, in the rampant occurrence regions, the average temperature in January is above -13.4℃, the annual temperature is above 3.9℃ and the annual average humidity is above 44.9%.According to the on-the-spot survey of harmed forests in Northeast China, North China and Northwest China, together with the standard of damage grade classification, the 139 common tree species in northern China are divided into 4 grades, 40 highly susceptive tree species, 4 susceptive tree species, 16 resistant tree species and 79 immune tree species. The various willow varieties showed different resistance to the insect. The thickness of vessel walls, the diameter of lignified cells,the thickness of lignified cell walls and the width of fibers of willow showed a positive correlation to its resistance to the insect. The moisture content in bark was significantly negatively correlated to the incubation rate of the insect. The amount of soluble sugar in phloem was found positively correlated to tree damage by the insect. The tannin content in phloem was negatively correlated to incubation rate and larva survival rate of the insect. Different poplar varieties showed different secondary metabolic products both in kind and amount.As for the control of the insect, ecological measures are preferential. Multi-tree species cooperation control model was applied. Stumps of harmed trees were grafted with insect resistant tree species or that both with resistance and hardiness. According to the species of longhorn beetle and occurrence situation in different places, the set up of isolation belts (1km for each) showed effective control results of the longhorn beetle both for tract forests and forest belts. These control measures are practically significant to the regeneration and improvement of the mature forests in the Three North shelter-forest region of China.
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