By Rick Howland
It’s probably just a matter of time before the emerald ash borer appears in a community
near you. Indigenous to China and unheard of in the U.S. and Canada until a decade
ago, the emerald ash borer, or EAB, was most likely a stow-away, sneaking into America
hidden in green ash used in dunnage, a packing material used in ocean-going shipping.
The beetle is believed to have arrived in the upper Midwest in the 1990s, but it
would be several years, 2002 in fact, before the deadly decline in ash trees would
be attributed to this voracious pest and steps were begun to stop its spread. Millions
of ash trees (true ash species only) in the Michigan, Illinois and Ohio regions
and into Canada have succumbed to the larvae, which devour their way through the
cambium, essentially girdling the trees and killing them.
Illegal and inadvertent
shipping of firewood and nursery stock have helped spread these insects far, wide
and fast. The first line of defense was and remains quarantine, preventing the transport
of ash and ash products (including firewood and mulch) across county lines. As the
summer came to a close, 18 counties in and around the Chicago area had been included
in the quarantine. Because ash can be difficult to differentiate from some other
hardwoods, especially for homeowners and other nonprofessionals, the cross-county
quarantine has come to include ALL hardwoods. In some areas in the Midwest, it is
illegal for a homeowner to take wood for a campfire from one place to another. Pine
and other softwoods are the exception. (Mulch is a bit of a question, because, depending
on the shred or chip, the processing may or may not be a self-eradicating process.)
On the one hand, regulations are in place at the federal, state and county levels
to prevent the physical spread of the EAB.
There is a question over the availability
of funds to battle the insect and also to enforce regulations, but if you get caught
in violation, fines can run about $500 per event. The experts we spoke with in state
and federal agencies, a leading academic on the subject at Michigan State University,
and equipment manufacturers all agree that getting the word out to tree care professionals
is critical, since the spread is accelerated, literally, by vehicular traffic and
equipment. Right now no protocols exist for equipment other than ensuring that NO
ash of any kind is onboard. How easy would it be to take an infested tree down in
one county, ship it back
to the yard, then re-ship it as firewood to another state where the prolific breeding
and devouring insect can take up new residency?
There is only one protocol that
would allow an arborist working in a quarantine area to move ash debris, and that
is the one-inch rule. While not absolutely agreed to by all the experts, it is generally
believed that the EAB larvae (the insect stage that does the cambium damage) cannot
survive chips or grindings of a 1-inch square or less. But you still may need clearance
or permission from a county, state or federal agency to move such chipped material,
so check first to avoid a potential fine. That, of course, begs the question of
the capabilities and conditions of your equipment. While “decontamination” is not
a requirement – at least so far – other than that equipment shall not carry ash
(or other hardwoods, in some cases), there are broader questions on the table of
natural resources regulators regarding levels of cleanliness of equipment.
There
is talk that pressure washing and possibly applying insecticides, antibacterial
or antifungal agents may become part of the protocols to curb contamination with
EAB and other invasives. The situation is still new, but with tree care companies’
service areas extending beyond county, state and regional lines, questions of liability
are likely to pop up. One question we asked, which has had little airing yet, revolves
around who is responsible if a previously pristine area is infested with EAB (or
other insects or biologicals)? Are you, the professional, responsible for the spread
of the disease, or does liability go back as far as the property (tree) owner? Some
of us will groan under the projected weight of compliance or due diligence. Others
will be thinking that the more they know, the more they can turn the situation to
their advantage. It’s the old Chinese definition of crisis – danger plus opportunity.
If you’re prepared, you may be able to work and take advantage of a situation where
others can’t comply. Anthony Weatherspoon, forest product specialist at the Michigan
Department of Natural Resources, is one of those at ground zero for the EAB problem.
“It’s big and getting bigger,” he says. “Usually, equipment does not contaminate,
because the ash borer is a cambium borer. The reasoning for grinding down to one-inch
or less is that such small
pieces will take care of the larvae; they won’t hatch during their egg period.”
The explanation is that they should be exposed to the elements where they dry up
and die or can’t hatch in a hostile, unprotected environment.
He explains that the
EAB lifeycle can be a long one, starting as early as May, depending on temperatures,
with the beetle flying and laying eggs into August, and larvae hatching and doing
their damage by girdling trees from August to October. But, even at the one-inch
chip size, EAB may still survive chipping and grinding. “Detection has been our
biggest problem,” Weatherspoon explains. “By the time we discovered it, the infestation
had already spread to a lot of places, and some of the new infestation areas had
not been previously looked at but are now recognized as EAB problem areas.” He recounts
one major firewood dealer in southeast Michigan who had been shipping ash to northern
Ohio, Indiana and Chicago for years before the source of the ash problem was accurately
identified. Right now, two things USDA APHIS (Animal and Plant Health Inspection
Service) agents are looking for transcends just the ash borer. They are beginning
to look at the practicality and need for sanitizing equipment against a host of
menaces, such as oak wilt. “Right now, all I can say (to tree care professionals
working in contaminated areas) is to make sure all bark and ash material is off
your machine before you go out of the quarantine area.” Equipment considerations
What are equipment manufacturers doing? The last thing manufacturers want is to
have their traveling equipment become the source of spread. “When it comes to the
emerald ash borer, brush cutters, stump cutters and tree spades all are involved
in this,” notes Mark Rieckhoff, Vermeer’s environmental segment manager for tree
care, maintenance and removal products. “We got involved with the Iowa Department
of Natural Resources. We were testing new machines at a state park and DNR was going
through the campgrounds informing local campers of EAB and firewood, telling them
not to import wood, but to buy locally to prevent the spread of the insect."
DNR advised the crew of the situation, and Vermeer has since been collaborating
with DNR in Iowa – before the insects arrive. Containment and quarantine have failed
to stem the spread thus far, and the insects have eluded authorities and migrated
from county to county. Iowa is working now to put plans in place so that, when and
if it crosses the Mississippi, they have a plan in place to react. (That’s expected
to be in the spring of ’08.) “We are collaborating any way we can with government
officials and our customers on manpower, machines and dealer support,” Reickhoff
says, “training our dealers throughout Iowa and Illinois regarding the EAB situation
and how Vermeer can assist the user (for example, ensuring that a chipper is set
and running properly to meet the one-inch chip requirement). We also are working
with state officials and private crews regarding appropriate practices, service
and support of our machines to ensure they help the user comply with quarantine
regulations.” Technically, he says “machines can’t be in violation of the quarantine,
only the materials onboard. We have to go out and test our own equipment every day
to ensure that they are not carrying quarantined material and that, in the case
of our chippers, that we are running to the one-inch requirement. We have to be
better stewards, too. We have people pulling equipment through nearly 100 counties
in Iowa alone,” Rieckhoff explains. “It’s so easy to pull a stumper or brush cutter
across multiple counties within a day. We, as a manufacturer, and our dealers need
to keep an eye on compliance.”
So, what else can the professional arborist
do? Can the EAB be stopped? Can you do anything for your customers and your business?
Possibly. David Smitley, professor of entomology and extension specialist at Michigan
State University, says the infestation is very active in western Ohio, northern
Indiana and hotspots in northern Illinois. “There does not seem to be any way to
stop it completely,” he says. “All true American ash trees are susceptible,” he
says, “and all (American) ash trees can die when the EAB moves in – every single
tree. Larvae tunnel under the bark and into the sapwood and completely destroy trees.”
(Smitley stresses that EAB attacks only true ash trees – not the mountain ash, which
is in the rose family.) “It doesn’t look like we can eradicate it from North America,”
Smitley warns, “because too large an area is infested. But we can slow the spread
by avoiding the movement of ash wood from infested to uninfested areas.”
Pointing
to the federal quarantines, he says, “We are seeking cooperation from tree care
professionals and even homeowners who take firewood camping not to move any ash
wood. The same holds for equipment going from infested to noninfested areas. Don’t
take any branches or log sections – or chips larger than an inch. “Certainly, the
beetles can fly and spread that way,” Smitley admits, “but the biggest threat is
in the transport of firewood; already there’s evidence of it showing up (in areas)
from Virginia and Maryland to Colorado. It’s the long-distance spread we are most
concerned with,” he says. The only exception to the quarantine is wood that has
had its bark stripped off and then has been identified, inspected and approved by
the USDA APHIS. Some of this is handled at the state level. Smitley is involved
in developing methods of protecting and saving ash trees via the use of insecticide
treatments.
“EAB is moving all across the Midwest, spreading every year. While we
cannot eradicate it, we have promising research that could save individual trees.
We originally thought there was no way to protect the trees, but we have developed
treatments – a soil drench (imidacloprid in water) – that does very well.” In fact,
the Michigan State University Extension Service held a field day on August 16 entitled
“Fighting Emerald Ash Borer...the SE MI Experience.” (See MSU Field Day link) It was an opportunity
for tree care professionals and educators outside southeast Michigan to see how
they could benefit from successes. Participants got the chance to walk the course
at the Bay Pointe Golf Club to see test results after four years of MSU field research
on soil drench treatments and trunk injections. According to Smitley, half the ash
trees (of all sizes) were treated, half were not (left as a control). “The half
that were treated look pretty good,” he says. “We want to start the process while
the trees are healthy,” he says. “People need to know they have a choice – even
helping mildly infested trees – although it gets shaky with the canopy thinning
out or dying back 50 percent. At that point it may be too late.” Sooner or later
the emerald ash borer will be in your marketplace.
Where and how compliance to ensure
containment and prevent contamination are effected at the local level remains a
work in progress. Federal regulations that required cutting every ash in the area
clearly haven’t worked. Suffice it to say, the tree care professional will need
to be up on the latest federal, state and county regulations – as well as what treatments
to recommend to clients. The smart ones will be ahead of the curve, knowing they
can benefit by promoting their compliant services.
TREE CARE INDUSTRY – SEPTEMBER 2007