Municipal Tree Board
Emerald Ash Borer
This Asian beetle, discovered in 2002 in southeastern Michigan and Windsor, Ontario, infests and kills North American ash species (Fraxinus sp.) including green, white, black and blue ash. Thus, all native ash trees are susceptible. Damage is caused by the larvae, which feed in tunnels (called galleries) in the phloem just below the bark. The serpentine galleries disrupt water and nutrient transport, causing branches, and eventually the entire tree, to die. Adult beetles leave distinctive D-shaped exit holes in the outer bark of the branches and the trunk. Adults are roughly 3/8 to 5/8 inch long with metallic green wing covers and a coppery red or purple abdomen. They may be present from late May through early September but are most common in June and July. Signs of infection include tree canopy dieback, yellowing, and browning of leaves. Most trees die within 1 to 4 years of becoming infested, unless treated. The Emerald Ash Borer has already destroyed 6 million ash trees in southeastern Michigan.
© 2012
Village Of Medina, Orleans County
