Emerald Ash Borer Program

Emerald ash borer (Agrilus planipennis Fairmaire) (EAB) has become the most destructive invasive forest insect in North America.  First identified as the cause of ash decline and mortality in Detroit, Michigan and Windsor, Ontario in 2002, this phloem-feeding buprestid has killed tens of millions of ash trees (Fraxinus spp.) in forest, rural and urban settings. 

Adult beetles nibble on ash leaves during the summer, but cause little damage.  EAB larvae, however, feed in S-shaped galleries in phloem which often score the outer sapwood.  Larval galleries disrupt nutrient and water transport, effectively girdling branches and entire trees.  Established EAB populations build and spread over time, but human transport of infested ash nursery trees, firewood or logs can lead to new infestations well beyond the existing core populations.  These discrete “outlier” sites are often not discovered until 4-6 years after establishment. 

After a new EAB outlier site is discovered, quarantines are imposed to limit the chance of infested ash material being moved further.  Residents, property owners and municipalities in the affected area, however, are left to fend for themselves.  If no action is taken, EAB populations in the outlier site will undoubtedly build and spread.  Ash mortality will progress and an ever-greater area will be faced with the economic and ecological impacts of EAB.  The current approach in EAB outlier sites could mean the demise of the North American ash resource, including at least 15 native ash species.

Girdled Ash Tree                                    Purple Trap in Tree

Click here to access the official Emerald Ash Borer web site.

Cooperation Emerald Ash Borer Project map - Click here

For more information about the Emerald Ash Program, contact:

Brenda Owen

Emerald Ash Borer SLAM Coordinator

500A Ferry Street

St. Ignace, Michigan  49781

brenda.owen@macd.org