Asian Longhorned Beetle Alert: Tree Injection
The goal of the injection program is to save trees. To date, over 4,200 trees have been removed on public and private property in New York City, and millions more are at risk. In fact, almost half of the estimated 5 million trees on public and private property in NYC are potential hosts to the beetle.
Even with intense tree survey, we are always one step behind the beetle (because we don't destroy trees until we know they are infested). Tree injection offers the possibility of getting one step ahead of the beetle.
We are pleased that the Animal and Plant Health Inspection Service (APHIS) of the USDA is dedicating resources to this important program. It is wholly funded by APHIS. In 2007, 66,016 trees were treated in NYC. In 2008, 66,736 trees were treated in NYC. These include trees on streets, in parks, and on private property.
Tree injections make the tree unpalatable to the beetle. Beetles that ingest the substance lose their appetites, and then die.
The treatment will greatly reduce the population of beetles in treated areas. Sick beetles may, however, lay eggs on trees before they die, so a treated tree is not completely immune to infestation.
We only inject trees that we believe are not already infested with the beetle. The goal is to create a large block of treated trees near or around infested areas that will serve as a barrier to the advancement of the beetle. Unfortunately, if a tree does become infested subsequent to treatment, it will still have to be removed and destroyed.
Imidacloprid (commercial name: Imicide®) is injected into the tree base via small plastic canisters and is dispersed throughout the tree's own circulatory system. The treatment is naturally absorbed into the tree, moving upward into stems, twigs, and foliage.
The first year of treatment was targeted for trees on the eastern and western edges of the infestation. To the east, this includes the Bayside and Flushing areas in Queens. Treatment areas on the western edge of the infestation include the land on both sides of the east river. In Manhattan, this includes areas of the Upper and Lower East sides. The treatment zone on the east side of the East River stretches from Fort Greene in Brooklyn to Long Island City in Queens.