Imidacloprid for halting spread of Asian long-horned beetle should be prohibited

Two environmental groups are urging the state pesticide board to deny a proposal to use a controversial insecticide in a particular way to halt the spread of the Asian long-horned beetle in Worcester.

The Toxics Action Center, based on Boston, and the SafeLawns Foundation, based in Washington, are asking the state to not allow the chemical, imidacloprid, to be applied to the soil around trees to kill the beetle.

While effective in killing the beetle, which has led to the destruction of 25,000 trees in a 66-square-mile zone in and around Worcester, the chemical has been banned in France and Germany where it has been linked to the deaths of honey bees.

The proposal, which will be considered by the board sometime this fall, calls for the soil around trees to be drenched with the pesticide so that it is drawn into the trees so that insects feeding on it will be killed.

Instead, the groups favor injecting affected trees with it to minimize unintended consequences.

"Certainly the Asian longhorn beetle is a devastating problem and no easy answers exist. Drenching your soil with this toxin, however, is most certainly not the solution," said Paul Tukey, founder of the SafeLawns Foundation.

"The impacts on bees, the soils and the watershed of that region could be devastating."

Injecting trees reduces the amount of toxin used and generally contains any poisons to within the tree, he said.

Made by Bayer, imidacloprid, sold under the name Gaucho in France, has been banned as a seed dressing for sunflowers in that country since 1999, after a third of French honeybees died following its widespread use.