EMERALD ASH BORER: SMALL INSECT, BIG PROBLEM!

Photo taken by Phil Nixon

WHAT IS THE EMERALD ASH BORER?

THE EMERALD ASH BORER (EAB) IS A SHINY GREEN INSECT THAT MEASURES ABOUT ½” LONG. IT BELONGS TO A GROUP OF BORER BEETLES CALLED BUPRESTIDS – THEY ARE QUITE COMMON THROUGHOUT THE WORLD.

Agrilus planipennis Fairmaire

THE LIFE CYCLE OF EAB

•The adult female lays eggs in the crevices of the ash tree bark. Newly hatched larvae bore through the bark and feed on the tree’s vascular tissue.

• As they grow, larvae zigzag through tree tissue, leaving S-shaped tunnels that are flat and wide and filled with frass (excrement).

Frass

Cambial tissue

Bark

• Larvae are creamy white with flat, broad shaped bodies and bell-shaped body segments.

• Mature larvae are about 1 inch long.

Larvae (August to April)

Pupae (April To Early May)• When warmer weather arrives,

larvae begin to pupate.• Newly formed adults remain under

the bark for 8 to 15 days as their outer “shells” harden.

Adults (May Through September)

Adults emergefrom the treethrough “D” shapedexit holes.

WHY IS THIS SMALL INSECT SUCH A BIG PROBLEM?

Range of ash in North America

Because….

there are ~150 million ash trees in Indiana forests.

And…

there are at least 1.5 million ash trees in urban areas in Indiana.

Black ash

ALL native North American ash trees are vulnerable to EAB.

Green ash

White ash

Blue ash

Once an ash tree is heavily infested with EAB, it will die within 1 to 3 years.

WHERE DID EAB COME FROM?

HOW DID EAB ARRIVE IN NORTH AMERICA?

EAB arrived in solid wood packing materials.

• Are manufactured from recently cut trees.

• Are not treated with heat or chemicals.

• Contain bark.

Wood packing material harbors bark- and wood-boring insects because they

often:

Once invasive wood borers make it to US ports, they have no trouble finding transportation to new areas.

WHEN DID EAB ARRIVE IN NORTH AMERICA?

EAB was first identified in the Detroit, Michigan and Windsor, Ontario areas in June of 2002, but it probably arrived in North America in the early 1990s.

In Asia, EAB has co-evolvedwith Asian ash trees. There arenatural enemies and pathogensthat keep EAB levels low. It is

Considered a SECONDARY pest.

WHY IS EAB A BIGGER PROBLEM IN NORTH

AMERICA THAN IN ASIA?

In North America, EAB has NOT co-evolved

with North American ash so there are no

natural enemies and pathogens to keep

populations of EAB in check. It is called a

PRIMARY pest.

• Natural spread of EAB is local (1/4 to 1/2 mile per year).

• Artificial or human-assisted spread moves the beetle much farther and faster in a less predictable manner.

How EAB Spreads

• ash firewood.• raw ash wood with

bark. • dunnage and crating

for heavy goods made from ash.

• ash nursery stock.• ash lumber and wood

with bark attached.

EAB larvae is often moved in:

PLEASE DO YOUR PART TO ARREST THAT PEST!

DON’T MOVE FIREWOOD!