Protecting Ash Trees from
the Emerald Ash Borer
Emerald Ash Borer infestation has been confirmed in Fort Thomas.
With its arrival, it is now time to take action and protect the
ash trees that can be saved. If no preventative control measures
are taken before or during the early stages of infestation, untreated
trees are certain to die, causing a safety hazard for any person
on that site.
What is the Emerald Ash Borer (EAB)? An Asiatic insect that
was inadvertently introduced into the United States via shipping
pallets from China. The first infestation was discovered near
Detroit, Michigan in 2002. Since then, EAB has spread throughout
many Midwest and Northeast states.
What does the EAB look like? EAB is a ½" long, bright
metallic green insect with flattened back.
What are the signs and symptoms of EAB infestation? EAB attacks
only ash tree species, starting at the top of the tree first.
Adult beetles begin to emerge in mid-May and females usually
begin laying eggs about 2 weeks after emergence. The eggs hatch
in about 2 weeks, and the larvae crawl under the bark and begin
feeding on the cambium and other tree tissues. As they destroy
these tissues, the first noticeable symptoms will be general
canopy dieback, sometimes with "watersprouts" forming
along the living portion of branches or trunk. Increased woodpecker
activity/damaged may also be seen. Short (3-5 inch) vertical
splits in the bark is another possible symptom. As the infestation
continues down the tree, direct observations can be made. The
larvae carve out winding S-shaped tunnels directly under the
bark. The adult borers create D-shaped exit holes.
What options are available to control EAB? There are limited
options available, each with its own advantages and disadvantages:
remove, replace, treat with insecticides, or do nothing (which
eventually results in removal anyway). Trees already infested
with EAB can still be treated with insecticides and perhaps saved
if they haven't yet lost more than 50% of their canopy. Some
of these insecticides are marketed for use by homeowners while
others are intended for use only by professional applicators.
How is the City controlling EAB? With the help of grant funds
from the Kentucky Division of Forestry and Northern Kentucky
Urban & Community Forestry Council, the Fort Thomas Tree
Commission has begun treating with insecticides the public ash
trees rated in good condition within heavy-use areas of the city.
These include public ash trees within the maintained areas of
the city parks as well as within street rights-of-way between
sidewalk and curb.
The Fort Thomas Tree Commission has contracted with Gregory
Forrest Lester, Inc., Tree Health Professionals, to apply the
initial treatments via trunk injection using the insecticide,
TREE-ageTM, which provides excellent control of EAB for at least
two years. This is a Restricted Use Pesticide that can only be
sold to and applied by a professional applicator.
What can private property owners do to control EAB on their
property? Similar to the public ash trees, it is important each
property owner with ash trees create their own plan and take
protective steps before it becomes too late. As
part of their successful bid on the public ash trees, Gregory
Forrest Lester, Inc. will offer residents of Fort Thomas a discounted
rate on application of the insecticide TREE-ageTM for the treatment
of ash trees on private property. When contacting them at (513)
351-6100, please indicate that you are a Fort Thomas ash tree
Homeowners also have the option to treat the trees themselves.
Look for an active ingredient called "Imidacloprid".
This is found in products such as Bayer Advanced Tree and Shrub
Insect Control, but any product with the active ingredient will
Apply in the Spring for best results, Mid to Late March and
no later than Easter. This treatment will have to be repeated
Use 1 oz per square inch of circumference of the tree. Mix
with 1-2 gallons of water and apply several feet away from the
trunk, approximaly 5' away.
For additional information, please contact the Campbell County
Extension Office at 572-2600 or visit the website at www.emeraldashborer.info