Emerald Ash Borer

The Emerald Ash Borer (EAB) was introduced into North America in the 1990s, and first documented in Connecticut in July of 2012. The affected towns were Prospect, Naugatuck, Beacon Falls, and Waterbury. Connecticut was the 16th state known to have the EAB. Infestations have also been found in southern Michigan, Ohio, northern Indiana, Maryland, Pennsylvania, Connecticut, New York, Massachusetts, and five others.

DEEP, the CT Agricultural Experiment Station, USDA, APHIS, and the US Forest Service are working together to define the extent of the infestations in Connecticut. DEEP has quarantined all infested ash tree materials from leaving New Haven County. Most ash trees are white ash. Ash trees are < 3% of the trees in Connecticut forests. Although 3% sounds small, the effect on the butterfly and moth population is large. Ash tree seeds are eaten by wood duck, bobwhite, purple finch, pine grosbeaks, and fox squirrel. Ash wood is desired in various markets for its strength and flexibility (including furniture and baseball bats).  

Ash trees exhibited crown dieback and dense sprouting from tree trunks. Most trees die within five years of being infested with EAB.

Emerald ash borer is a small green (0.3-0.5 inch in length) green metallic beetle that belongs to a larger family of beetles known as Buprestidae (metallic wood-boring beetles). The beetle lifecycle takes 1-2 years to complete.

The EAB undergoes a complete metamorphosis. A complete metamorphosis is as follows: Egg, Larva or grub, pupa, adult. The EAB has 4 growth phases or instars.  Adults emerge in the middle of June and continue for approximately 5 weeks. The female lays her eggs on the bark of the ash tree. At 7-10 days the eggs begin hatching and the larvae travel to the inside bark and begin feeding. Feeding takes place on the inner bark called the phloem and the cambium (new wood generation). The phloem is the part of the tree that carries the sugar nutrients from the leaves to the roots. The adult EAB feeds on the leaves A definite sign of EAB infestation is a D-shaped exit hole in the ash tree. S-shaped tunnels are signs of the burrowing larvae. An increased volume of woodpecker activity searching for grubs.

Three main techniques focus on locating EAB infested trees: Trap trees, purple lures, and biosurveillance. Trap trees are existing ash trees that are stripped of bark around the entire ash tree. The girdled tree sends out a chemical that draws any insect to feed on the stressed tree. The purple trap (AKA “Barney Traps”) are a vivid purple color. The trap is coated with a pheromone attracts the EAB. The walls of the trap are coated with sticky paper to which the EABs become attached. Biosurveillance is nature’s way of naturally killing the EAB. The native non-stinging wasp hunts for any metallic wood boring beetle and brings it back to the nest to feed to its young.

The focus in Connecticut is to prevent the spread of the EAB by managing and or reducing its numbers.

Please report suspected EAB sightings to the CT Agricultural Experiment Station at 203.974.8474 or CAES.StateEntomologist@ct.gov. Send any EAB sightings via a digital photo and leave an address of the EAB sighting.

Article: State Alert on Imported Insect