Insecticide To Be Tested On Asian Longhorned Beetle

Merit is to be tried on 240 non-infested trees – in four different areas of 60 trees each – in the Ravenswood suburb of Chicago. Ravenswood is the area of the heaviest infestation in the city and is under a USDA quarantine that restricts movement of wood and related agricultural products from the area. In fact the USDA recently expanded the Asian long-horned beetle quarantine to include more parts of Chicago as well as two more areas in nearby Cook County after inspections revealed that the beetle had infested trees outside of the previously regulated areas.

In each area of 60 uninfected trees, the insecticide Merit will be injected into the soil around 15 trees and injected into the trunks of 15 others. The remaining 30 trees will be controls to compare their experience to that of the treated trees.

Federal tree and insect experts were to meet with city and state beetle battlers Feb. 17 to figure out where, when and exactly how they will run the tests. McLane said they will have to guard injected trees while the little bottles of pesticide drain for a number of hours so children or animals don’t grab the containers and drink the poison.

Officials hope Merit might be able to protect trees that haven’t been attacked yet by the beetle, which arrived here and in New York in fresh-cut wood packing material from China. Similar tests are being planned for New York City and Long Island, the only other U.S. areas known to be infested.

Since July 1998, Chicago has lost 1,190 trees to the beetle, which does its damage when in larval form by chewing tunnels through the heartwood. Tests of various systemic insecticides in China the last two summers by U.S. and Chinese scientists found that when injected into the soil or tree trunk, Merit "appeared to be the most effective against not only adult beetles, but against the young larvae," McLane said.