First Signs of Emerald Ash Borer Damage Observed at White Memorial

Emerald ash borer is a highly invasive insect that was introduced from Asia and was first detected at White Memorial in 2014.  White Memorial staff and volunteers utilized a variety of surveillance programs starting in 2012 including Cerceris wasp biosurveillance, double-decker purple prism traps, and encouraging USDA and UCONN to install canopy purple prism traps throughout the property.  We observed our first signs of Emerald Ash Borer damage on the property during the winter of 2016 and 2017.  The damage is caused by woodpeckers picking at the bark of ash trees exposing the lighter-colored underbark to acquire EAB larvae living under the bark.  This pattern is commonly referred to as "blonding".  Blonding is often observed in the canopy of the trees first since that is where the adults often lay their eggs and where the larvae start to feed under the bark.  We often see blonding along the southern aspect of the tree trunk which is likely the preferred location for adults to lay their eggs so that larvae develop faster on the warmer side of the tree.

White ash (Fraxinus americanus) blonding caused by woodpeckers searching
for Emerald Ash Borer (Agrilus planipennis) larvae.

Blonding can be observed along the entire length of the tree trunk, from canopy to ground.

Close-up view of white ash tree blonding.

Close-up view of Emerald Ash Borer exit hole (D-shaped hole) which is evidence of adults emerging from this tree.