Emerald Ash Borer Fact Sheet 2014
Emerald Ash Borer (EAB) is native to Asia. It
was probably imported into Michigan 10-15
years ago via shipping containers.
was discovered during June 2002 in south east Michigan.
Since then, more than forty million Ash trees have been infested and
killed in the United States.
The EAB is
predicted to cause an unprecedented $10 – 20 billion in losses in urban forests
over the next ten years.
A study by
the U. S. Forest Service found there to be more than 3.8 billion White Ash
trees in Ohio.
The EAB is
now the most invasive insect in North America.
the EAB has been found in 72 of 88 counties (as of December 2013), including
Clark, Greene, Miami, Montgomery and Warren counties.
If the EAB
is found within 15 miles of your location you need to consider your options,
1) treat ash
trees with insecticides.
2) remove ash
ash trees and replace with another non ash tree.
If a tree
has less than 50% canopy decline it may be worth trying to save.
infested with EAB do not show symptoms until 1 - 4 years after infestation.
Not all ash
trees are worth saving. Make an
assessment of your property. Save trees
that provide shade for your home, are a focal point in the landscape and provide
high value to your property.
The life cycle of the EAB:
emerges from infested trees in late May through early August. As they emerge, they leave a small D shaped
exit hole in the trunk. Adults live 3-6
weeks, feeding on Ash leaves (which cause no damage to the tree). The female will lay approximately 50 -100
eggs on the bark surface. When the eggs
hatch the larvae will tunnel into the tree, where they feed on the phloem and
outer sapwood, disrupting the flow of nutrients and water between the canopy
and roots. This is what causes eventual death to the tree. Larvae continue to feed through the summer
and into autumn. They over-winter and in
the spring pupation occurs. Adults
emerge to complete a typical one year life cycle.
Signs and symptoms of EAB
infestations are usually difficult to detect until they become severe because
the larvae are under the bark and adults spend most of their time in the upper
canopy of the tree. On larger trees, EAB
usually colonizes the upper trunk area, making diagnosis difficult from the
ground. Small, vertical bark splits can
occur when the larvae are present. These
splits can be enlarged to reveal larvae and galleries (the S shaped feeding
pattern). Also look for D shaped exit
holes in the trunk or large branches.
Branch dieback and canopy thinning will start from the top of the
tree. Sucker growth (epicormic shoots)
from the main trunk is also an indication of EAB presence, as is increased
woodpecker activity. Complete tree death
occurs within two to four years of initial infestation.
Will the EAB kill other
infests only ash trees. Those found in Ohio include: Black Ash (Fraxinus nigra), Green Ash (F.
pennsylvanica), White Ash (F. americana) and Blue
Ash (F. quadrangulata).
The EAB will
not infest Korean Mountainash (Sorbus
alinifolia) or European Mountainash (S.
Is it less expensive to
remove the tree than treat it?
ash trees may be more expensive than treatments. A large ash tree located near
a building may cost as much as $2,000.00 to remove. Keep in mind that if you want a new tree
where the ash was removed there is also the expense of a backhoe to dig out the
ash stump. The loss of a large tree may significantly reduce property
value. Visit www.treebenefits.com, this
will help you determine the economic value your ash tree provides to your
This fact sheet has been written by Steve Kuflewski, founder and owner of Village Landscaping LLC. Graduate of The Ohio State University, College of Agriculture, Department of Landscape Horticulture, 1977.
This information has been gathered from many sources, including: extension publications from The Ohio State University, Michigan State University, Purdue University, Penn State University, University of Illinois, University of Wisconsin; The American Nurseryman; webinars; seminars; and various web sites.
Click here for Signs and Symptoms of Emerald Ash Borer.