Impacts of chipping on surrogates for the longhorned beetle Anoplophora glabripennis (Coleoptera : Cerambycidae) in logs

As part of the eradication program for recent introductions of the longhorn ed beetle Anoplophora glabripennis (Motschulsky) in the United States, wood from infested trees is chipped and incinerated. Two tests were conducted t o evaluate the efficiency of chipping wood from infested trees on the survi val of the beetle. In the first test, plastic worms were used as surrogates for larvae of the beetle. Plastic worms of different sizes were placed in holes drilled in logs of sugar maple, Acer saccharum Marsh. In a second tes t, in addition to plastic worms, we used different instars and pupae of gyp sy moth, Lymantria dispar (L.) (Lepidoptera: Lymantriidae); larvae of the b eetle Phyllophaga annina Lewis (Coleoptera: Scarabaeidae); and larvae of an unidentified weevil (Coleoptera: Curculionidae). Although chipping did not result in an obvious damage to all plastic worms, it did kill all larvae a nd pupae of insects placed in holes of maple logs. The overall recovery rat e (percent recovered) for the plastic worms war; 96% in the first (1997) te st and 71 and 98% for 10 and 40 mm long plastic worms in the second (1998) test, respectively. Logistic regression analysis of the data from the first experiment indicates that larger worms receive more severe damage. Size of logs did not have a significant effect on the level of damage received by plastic worms. All recovered insects were severely damaged after chipping l ags and we could not determine recovery rates. Results of the two tests ind icate that chipping wood from infested trees without incineration of the re sulting chips provides a highly effective method for destroying wood inhabi ting insect pests such as A. glabripennis. The elimination of incineration saves considerable resources while effectively eliminating risks associated with movements of wood containing living wood-boring insects.