Emerald Ash Borer - We have seen it coming
Emerald ash borer is a destructive insect feeding on and eventually killing ash trees. It was first noted in Michigan in 2002, but experts are convinced it entered the US and began attacks years before damage was noticed. The years since 2002 have allowed arborists at Genesee Tree Service to follow the university and government efforts in each state involved, to learn what has worked to slow the borer. So when the borer was detected in NY state in 2009, GTS was ready to deal with the EAB.

Initial attacks tested control methods
In the first years after discovery of EAB in America, it was thought that the only means of controlling its spread was removing trees in advance of the beetle. Canadian efforts removing ash trees in a 10 kilometer- wide "suppression" zone in Ontario province proved ineffective as the beetle jumped the gap and moved onward to current presence in Toronto and Ottawa.

Insecticide use against the pest was studied for different chemicals and varying application methods. Results published in 2005, 2007 and since demonstrated a range of borer control success for insecticides applied by spray, root zone drench or trunk injection. Treatment became a proven option and changed views away from the doomsday messages of ash extinction publicized in the early years of the efforts.

A Superior Insecticide Approach
Arborists at GTS followed efforts in Midwestern states, and began preparation of a response before EAB reached New York's western border. Groups of insecticide-treated trees have survived even when under "insect pressure", surrounded by untreated, infested ashes. We saw in the university studies that systemic use of trunk- injected insecticides were equal or better controls than sprays or root drenches.

Trunk injection is superior considering:

• spraying encounters problems with large trees, nearby buildings, parks or bodies of water
• drench effectiveness varies with ground moisture, heavy (clay) soils and weather
• trunk injection delivers insecticide to tree circulatory tissue without exposing humans & beneficial insects to chemicals

Genesee Tree uses the ArborJet "closed" system to deliver insecticide without exposure to air or soil. Injection through the trunk is by a one-way miniature plug that prevents leakage and allows healing through bark growth over the plug. From our study of insecticide trials, GTS chose emamectin benzoate, sold as Tree-Äge, as the best chemical investment for our clients.

Tree-Äge is superior in several ways:

• Effectiveness near 100% as reported by US Forest Service
• Provides 2 to 3 year control per injection
• Chemical described "persistent in tree tissue, relatively immobile in the environment"
• Outside the tree tissues, emamectin benzoate breaks down rapidly with microbial activity and sunlight, and is considered an insecticide compatible with integrated pest management (IPM) programs

GTS found the superior combination of Tree-Äge insecticide and application by trunk injection met our standards for environmental stewardship and performance goals for Rochester customers.