the beetle was introduced to North America from China probably in the 1990’s but was not discovered until 2002 when it was found in Michigan and southwest Ontario in Essex County
since then it has been found in Ohio, Maryland, Virginia, Indiana, Illinois, and Pennsylvania
Biology
adult beetles are shiny green and 8-13 mm long (1/2 in)
mature larvae are whitish and 26-32 mm (1-1 ¼ in)
adults generally emerge in spring and summer and lay eggs during this period
the beetle requires one or two years to develop from egg to adult
adults and larvae can travel on firewood and nursery stock
larvae tunnel under the outer bark and create serpentine feeding ‘galleries’
infected trees show yellowing and loss of leaves in the canopy, and suckers growing from the base of the trunk
gradually, the damage spreads to the rest of the tree which eventually dies
suckers that resprout from the base can live for several years
Impact on Trees
able to attack and kill healthy trees
all native and introduced ash trees are susceptible
ash trees are very widely planted
the larvae consume the inner bark which strangles the tree
infected trees die within one or two years
southwestern Ontario from Windsor to London has been severely affected by the beetle where hundreds of thousands of ash trees have been killed
the larvae feed under the bark and the adult’s exit holes are very small making infestations difficult to detect early
the main strategy has been to remove and destroy all ash trees in the area of an infestation and prohibit movement of any ash trees or firewood from the infested area
a pilot study is underway involving a parasitic wasp