What is the Emerald Ash Borer?

Historic, Archive Document

Do not assume content reflects current
scientific knowledge, policies, or practices.

The emerald ash borer,

Agrilus planipennis Fairmaire, a
beetle native to Asia, was first
detected in Michigan in 2002.

Evidence suggests that the beetle
was established in Michigan for
a number of years prior to its
discovery. Emerald ash borer
has since been detected in Ohio,

Indiana, Virginia, Maryland,
and Ontario, Canada. In addition to
spreading by natural means, emerald ash
borer can be transported to new areas in infested
firewood, timber, and nursery stock. The beetle
is responsible for the loss of more than 7 million
ash trees in Michigan alone.

Actual Size

Larva

S-Shaped Galleries

D-Shaped
Emergence
Hole

Biology:

Eggs are laid between layers of bark and in
bark crevices. Larvae hatch in about one week
and bore into the tree where they feed on the
inner bark and phloem, creating “S” -shaped
galleries. The larvae go through three

feeding stages, and then excavate a
pupal chamber in the fall, where
they will overwinter as prepupae.
Pupation occurs in late spring, and
adults begin to emerge through “D”-
shaped exit holes in May and early
June. Adults will remain active until the
end of summer.

This commonly encountered beetle (The Six-
spotted green tiger beetle Cicindela sexguttata )
is often mistaken for EAB due to its similar
appearence. It is a predator of small insects and
is usually found on woodland trails.

Host:

In North America,
emerald ash borer
is known to infest
all species of ash
( Fraxinus spp.).
Ash can be
recognized by
the presence
of compound
leaves which are
arranged opposite
of one another on
the branches.

Photographs: James W. Smith, David Cappaert, www.invasive.org and PA DCNR.

Signs and Symptoms:

New infestations are difficult to detect, as
damage to the tree may not be apparent for up to
three years. Signs of older infestation can include
branch dieback in the upper crown, excessive
epicormic branching on the tree trunk, vertical
bark slits and woodpecker damage.

Dieback

Bark Slits

Epicormic branching

Woodpecker Damage

Other Stressors

Ash may also be stressed by
drought, diseases such as ash
yellows, and by native insects
like the redheaded ash borer,
Neoclytus acuminatus ,
(Fabricius) which creates a
round emergence hole. /

Redheaded Ash Borer

Protect our
Forests and Trees.

Help Stop the Movement
of Exotic Pests.

DO NOT MOVE
FIREWOOD!

Exotic pests like the emerald ash borer
can be spread when infested firewood is
transported to new areas.

• Use LOCAL firewood

• Do not bring firewood from
home

• If you have already transported
firewood, do not take it home,
do not leave it - BURN IT!

If you think you
have found emerald ash borer,
report it by contacting:

PA Department of Agriculture:
1-866-253-7189

PA Department of Conservation and
Natural Resources (DCNR)

Penn State Cooperative Extension:
or

United States
Department of Agriculture

OR

Report your sighting by
e-mail at:

Badbug @ state.pa.us

NATIONAL AGRICULTURAL LIBRARY

Pennsylvania Department of

AGRICULTURE

1

PA Department of Conservation and Natural Resources

pennState _

Penn State Cooperative Extension

jjuA united States Department of Agriculture

The USDA is an equal opportunity provider and employer. FS-808c