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Hi everyone, I'm from Essex county (borders Chatham), and I can tell you that just about 99% of the ash trees around here have been infected with the EAB!!!!!!!!! By the time you realize the tree is infected...its to late to try & save it. This past spring, I was at a Home & Garden show in Windsor,Ontario (1/2 hour from my place), and spoke to a rep from the Canadian Food Inspection Agency. She had indicated to me that there wasn't anything that anyone knows of that will take care of the ash bores. The 2km strip of land being cleared of ash trees outside of Essex county was an attempe to delay their migration in hopes a solution could be found. She also said that Essex county was a lost cause and nothing could be done about it. For more info on EAB, visit (www.inspection.ga.ca). If removing an ash tree in this area, it can NOT be dumped at the land fill. It is recomended that all ash wood material be delivered to the CFIA Ash Wood Deposit Site Located in Windsors west end, (between the Windsor Raceway & the Detriot River). The phone number for the CFIA Essex office: (519) 776-5483 / Outside Essex County: 1(866)463-6017 :blob2: I have customers that had planted nothing but ash trees on their property years ago only to find out that thier investment had died due to the EAB. What a shame :angry:
 
Was out all morning doing quotes. Yup, you guessed it...all dead ash trees. :( Its like telling people that thier family pet just got hit by a car and will not make it. One person said that they would like to keep the tree as long a possable and have it taken down in a couple years. I explained to her that she has a pool under the tree and once it dries out and becomes brittle, a branch could break off and fall like a lawn dart, landing in the pool damaging her liner etc. :eek: Not a lot of fun telling people bad news but what else can you do!
 
Catching back up again.

This seems like a no-brainer...
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Out of the ashes

Different uses are being explored for uninfested cores of trees

Wednesday, August 11, 2004BY MARIANNE RZEPKA

News Staff Reporter

Millions of ash trees - dying or dead - have been chopped down, then chipped or burned as part of a campaign to stamp out the emerald ash borer.

But the insect infests only the layer of wood just under the bark, leaving the core perfectly good. And some see chipping that core as a big waste of otherwise good hardwood, a hardwood so strong it's traditionally used for things like tool handles and baseball bats.

Several programs funded by a federal grant are looking for ways to use the bug-free wood for things like railroad ties, flooring and cabinets - creating exceptions to the quarantine that has kept wood in the known infested areas.

"There are a whole host of options out there," says Jessica Simons, who is overseeing the projects for the Southeast Michigan Resource, Conservation and Development Council, a nonprofit organization working on the project for the U.S. Department of Agriculture.

In the long run, she says, there could be new markets for using all the trees taken down by cities and counties on a regular basis, then simply turned into wood chips. "We're hoping to use this ash issue to recycle all the urban wood in southeastern Michigan," she says.

An estimated 8 million ash trees have been cut because of the emerald ash borer, a native of Asia that began destroying the trees in Canton Township two years ago.

Currently, some or all of 10 counties - including all of Washtenaw, Livingston and Wayne counties - are part of the core infestation. That area, plus three adjacent counties and five separate sites in the state, have been quarantined, which means no ash trees and ash wood can be transported outside that zone for fear of spreading the pest.

The state has set up seven disposal sites where the trees can be chipped, with the wood then transported to a burner near Flint to generate electricity.

In order to find other uses for the wood, the U.S. Department of Agriculture has distributed grants of up to $50,000 to four programs that include removing the trees - Detroit alone has more than 40,000 trees - to move more trees to milling sites and turn much of that wood into usable products.

Milling, not chipping

The Lamont Brothers Tree Service, in Whitmore Lake, has used its $50,000 grant to set up a milling program, with one mill in operation in Waterford, west of Pontiac, another being set up in Whitmore Lake, says Lee Kitzman, the company's project manager.

Previously, the company removed trees at homes and for developers; the wood was chipped and offered as mulch or sold as firewood. Kitzman says the company had a small milling operation for local wood artisans.

With the appearance of the emerald ash borer, Lamont Brothers became a designated site for the disposal of the downed ash trees.

Using the grant money, the company has set up the mill in Waterford, where the logs - ash or any other wood that meets specifications for grain - can be cut into boards and into railroad ties, that will be sent to a treatment plant in Wisconsin, Kitzman says. The state would have to inspect the wood under a special agreement with the company to transport the ties to Wisconsin, according to the Michigan Department of Agriculture.

Already, the firm has hired another employee for the work and may hire another, Kitzman says. Once the program is up and running, the company will almost double its current staff of nine employees, he says.

Lamont Brothers is looking at opening another milling site in Detroit, a move that would overlap with plans by the city to contract out that work using another $50,000 RC&D grant.

With a milling site in the city, it's estimated Detroit could save about $100,000 annually in costs now spent to transport downed ash trees to chipping sites.

Detroit figures estimate that 1,300 trees a year could provide more than 3,380 street barricades, 43 picnic tables, 24 bleachers and another 200 items like benches, signs, planters and shelving.

One tree at a time

Chris Last is working on milling trees on a smaller scale.

He is the owner and operator of Last Chance Logs and Lumber, headquartered in Livonia, a company he founded two years ago on an idea that grew out of his job as a municipal forester in Oakland County.

"I've always seen these beautiful (trees) being ground up, even before they confirmed the ash borer was an epidemic," he says.

Last used his $50,000 grant to buy a portable mill, a hydraulic loader and a kiln, which is being built at his yard in Howell. With the equipment, he can go anywhere there's a fallen tree and cut it up on the spot.

That can be someone's house or a municipal yard, says Last.

A recent customer called and wanted a cherry tree in her yard cut into boards so her son could make her an end table. There was so much wood, "I told her she could have a whole bedroom set," Last says.

Another woman, whose old red oak tree died, had it cut up and made into chests for her children.

He also works with cities and counties to mill logs they might have. Normally, Last says, municipalities will pile up a certain number of downed trees, then call in a grinder that could charge $325 an hour for a two- or three-day job. "All the municipality gets is a bill and a big pile of wood chips, that it has to pay someone to take away," he says.

Last's company saws the logs into wood that could be made into things like picnic tables. What they don't use, they can sell, to recoup some of the costs, he says. Last says he charges mileage and $70 an hour.

His goal, says Last, is to set a national precedent for what he calls "tree-cycling," using downed trees for a variety of items, including pool cues and church pews. "I even saw one gentleman made an old English-style treehouse from ash," he says.

Other uses for ash trees

Meanwhile, Michigan State University's School of Forestry is looking for ways to treat the ash logs and to use them with its $38,126 grant from the RC&D.

Research will be started to see the best way to kill the emerald ash borers on ash logs, says Pascal Nzokou, research associate in Wood Science who is helping with the project. That could help with transporting the logs out of the quarantined area.

And the school will be subcontracting with experts to find ways of using the wood, such as for flooring, paneling, yard furniture and cabinets, he says. A project team even visited a factory that manufactures baseball bats to see if there was any interest in using the ash wood, which has a grain similar to oak, says Nzokou.

When the emerald ash borer's destruction first became apparent, says Nzokou, "people were so concerned about spreading the bugs around that no one tried to do anything (with the wood)." However, he adds, the borer doesn't go more than a quarter of an inch into the wood itself, destroying only the layer under the bark, the layer that delivers nutrients to the branches.

In addition to overseeing these project, the RC&D is looking for a contractor to do a survey of trees throughout the state, says Simons. "This way we can actually quantify how much is out there," she says. "So the next thing that pops up, we're prepared."

Marianne Rzepka can be reached at (734) 994-6820 or [email protected].

© 2004 Ann Arbor News. Used with permission

Copyright 2004 Michigan Live. All Rights Reserved.
 
Aug. 28, 2004. 01:00 AM

Michigan tackles emerald ash borer
Proposed barrier may leave Ontario vulnerable

Firebreak would be 10 times longer than province's

PAT CURRIE
SPECIAL TO THE STAR

In the escalating war against the tree-killing emerald ash borer, Michigan is considering a massive firebreak 10 times as long, and up to eight times as wide, as the expansive ash-free zone hacked across Southwestern Ontario earlier this year.

But the state's plan, which would largely rely on voluntary landowner compliance, could leave parts of the province vulnerable to infestation.

"It's on the table," said Ken Rauscher, of Michigan's Department of Agriculture. And the goal of the campaign, which could take up to 15 years, is "total eradication."

Rauscher, director of pesticide and plant management, said he has "no idea" how much the Michigan barrier would cost or how many ash trees would have to be sacrificed to create an ash-free zone too wide for egg-laying female beetles to fly across.

Their tiny eggs hatch into larvae that bore through the bark and eat their way through the host tree's life-support system. With no known natural predators in North America, the insects have killed 8 million ash trees in Michigan and another 1 million in Ontario since they were first identified in Detroit and Windsor in 2002. Scientists believe they may have arrived in the Detroit area five years earlier, in infested wood shipping pallets or crates.

In February, the Canadian Food Inspection Agency (CFIA) spent about $10 million (Canadian) to destroy 88,00 ash trees, creating an ash-free cordon 30 kilometres long and 10 kilometres wide across the western edge of Chatham-Kent, between Lake St. Clair and Lake Erie.

The proposed Michigan corridor would be 300 kilometres long and 50 to 80 kilometres wide, says Rauscher. It would loop from Saginaw Bay to Lake Erie, cutting off Detroit and 13 surrounding counties that make up the heavily infested core area.

While the CFIA was able to override landowner protests in the nearly treeless Chatham-Kent corridor, Michigan would depend on "some type of volunteer private-owner management plan to reduce ash all along the zone, taking as much advantage of open farmland as possible," Rauscher said.

"Whether there would be some type of incentive (to get them to cut down their ash trees), I don't know."

There are some serious concerns about Michigan's strategy.

Studies by the U.S. Forestry Service suggest that emerald ash borers (EAB) are not confined to northern forests, but may be a warmer-climate species capable of preying on other kinds of trees as well.

``It seems they just really don't have a handle on it,'' said Kennon Johnson, resource protection manager for Walpole Island First Nation. ``I don't think there's anything anybody can do.''

The reserve is now on the frontline of a threatening new EAB invasion from Michigan. The insects have spread far enough north to threaten a new invasion of Ontario, north of Lake St. Clair, crossing into much more heavily-treed Lambton County, where much of the tree-cover is ash.

"We're taking this seriously. We could lose a third of our forest canopy. That would be devastating,'' said Walpole Island environmental officer Dave White.

"A lot of people think this thing can be eradicated. It's long past that,'' said scientist David Roberts, a professor at Michigan State University, who was raised the EAB alarm two years ago.

Any effort to establish a cordon sanitaire to contain infestation can be too easily thwarted by people moving infested firewood to cottage and camps.

"Containing the bug would be a possibility if we had a real, effective quarantine.

``We don't. People are taking firewood out of the quarantine area on a daily basis. A lot of people aren't aware of the quarantine and there are people who are actively ignoring it," said Roberts.

"It's time for a new approach.''

Rauscher agreed that the war against the EAB has escalated. ``The national allocation this year is $43 million (U.S.), and Michigan has allocated $27 million this year,'' he said.

Most of Michigan's EAB spending has come from the U.S. Department of Agriculture.

Apart from stamping out isolated EAB outbreaks in Ohio, Indiana, Maryland and Virginia, Rauscher said the federal money has been spent on Michigan's current strategy â?? quarantining all 50 counties of the Lower Peninsula (forbidding all movement of ash), cutting down every infested tree and every ash within 500 yards and spreading 10,000 sticky traps to snare egg-laying female ash borers.

While Michigan has 100 inspectors in the field looking for new infestations, on Walpole Island, Johnson is one of only two part-time inspectors. Both are resource protection officers trained by the CFIA to watch the reserve's trees for signs of infestation.

Despite small, isolated speckles of infection that have been identified and stamped out south of Chatham, the Chatham-Kent barrier is doing its job, according to Ken Marchant, CFIA tree specialist.

"Without it, the bug would just go roaring through," Marchant said. It would kill an estimated billion ash trees in Ontario and uncounted billions more all the way to the Atlantic Ocean.

"We knew it would be bad, but nothing like what I've seen," Marchant said, during a recent visit to an agency field office near Essex.

"I can't believe it. There are hundreds of thousands of dead and dying trees all across Essex County."

The focus now in Windsor-Essex is on a drive to replace the vanishing ash with a million seedlings of species the EAB shuns. Michigan also has been planting replacements for lost ash â?? which were originally planted to replace great stands of elm trees wiped out by Dutch elm disease 30 years ago â?? but these efforts could prove futile if the EAB switches to a new host species once it has killed all the ash.

Marchant believes the Chatham-Kent firebreak may buy time for Canadian and American scientists to come up with an antidote to the EAB. Because potential chemical pesticides are too expensive and too environmentally dangerous, any cure "will likely be biological; we hope for more information this fall," he said.

He said several teams of scientists are in China "looking for what attacks the beetle, but even if they find one it would be at least two years before we could be certain there would be no unexpected problems with it here.''
 
Michigan, Ohio crack down on firewood ban, set up checkpoints

September 2, 2004, 4:26 PM

SYLVANIA, Ohio (AP) -- State highway patrol troopers stopped cars and campers at road checkpoints Thursday along the Ohio-Michigan state line.

They weren't looking for drunk drivers or drugs -- just firewood.

Ohio started a ban last September on bringing firewood into the state from Michigan where a tree-killing beetle no larger than a small paperclip has killed or infested 8 million ash trees.

"People are going to be very surprised to have checkpoints at the state line," said Craig Stough, mayor of Sylvania, a Toledo suburb. "But it's a critical enough issue that we need to stop traffic."

Authorities handed out pamphlets explaining problems with the ash pest to 300 cars in three hours Thursday afternoon at one of two checkpoints. They searched a handful of cars and confiscated one load of firewood.

Sally Rochotte, of Blissfield, Mich., said she was a little surprised that she was stopped and asked whether she was carrying firewood. Inspectors decided not to search her minivan.

"I guess we didn't look like we were going camping," she said.

Michigan officials also have established checkpoints at highway rest stops around the state this Labor Day weekend to enforce a quarantine on moving firewood from 13 state counties.

Wood from the counties, covering parts of the southeast and south-central Lower Peninsula, has been quarantined to help prevent the spread of the emerald ash borer.

"Successful eradication efforts of this invasive exotic beetle hinge upon the cooperation of every Michigan resident," said Patricia Lockwood, Michigan's emerald ash borer policy director. "We will be out in full force to ensure travelers are not moving firewood."

The quarantined Michigan counties are Genesee, Ingham, Jackson, Lapeer, Lenawee, Livingston, Macomb, Monroe, Oakland, St. Clair, Shiawassee, Washtenaw and Wayne.

Michigan has been checking vehicles at highway rest stops for more than a year -- mainly around warm weather holidays and hunting season.

At four checkpoints during Memorial Day weekend this year, inspectors found 101 vehicles that were taking firewood out of quarantine area, said Sara Linsmeier-Wurfel, spokeswoman for the Michigan Department of Agriculture.

All of the wood was taken away and chipped into bits, she said.

"It still shows firewood is coming," said Linsmeier-Wurfel. "A lot of times families are taking wood up north."

Ohio Agriculture Department officials think firewood is at least partially to blame for the spread of the ash pest into the state, where it has killed thousands of trees mainly in northwest Ohio. The state cut down thousands more to try to stop the spread.

The firewood checkpoints, the first in Ohio, are targeting campers and people traveling for the Labor Day weekend, said Melanie Wilt, spokeswoman for the Agriculture Department.

They operate much like DUI checkpoints that are popular with police departments nationwide. Troopers and local police randomly stopped vehicles and searched their trunks for firewood.

If they find any wood, it will be confiscated. Although authorities could issue fines of up to $10,000 for violating the firewood ban, they plan only to give out warnings and confiscate wood, Wilt said.

"Our goal is not to ruin the holiday of vacationers," she said. "It's a big camping weekend so we see it as a good opportunity to educate people about the quarantine."

The two checkpoint sites, which will continue through Friday, are on secondary roads in the Toledo area. The state decided against putting checkpoints on highways to limit the traffic disruption, Wilt said.

"To set up a true quarantine between here and Michigan involves a lot of roads," Stough said. "They're not trying to stop contraband. They're trying inform people."

Researchers fear that if the ash borer spreads, it could lead to widespread devastation much like Dutch elm disease, which ravaged more than half the nation's elm population after being discovered in Ohio in the 1930s.

Many towns that lost elm trees replaced them with ash trees, thought to be a hardy and disease-resistant.
 
This is a long article, I'll break it up into 2 sections to ensure it's under the maximum character count. Even though it's long, it's still a VERY good summary on the EAB to this point.
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The Emerald Ash Borer Invasion:

Current Status of the Infestation and the Program to Eradicate It



Dr. Daniel A. Herms

Department of Entomology

The Ohio State University

Ohio Agricultural Research and Development Center

Wooster, OH 44691



Dr. Deborah G. McCullough

Departments of Entomology and Forestry

Michigan State University

East Lansing, MI 48824



Dr. David R. Smitley

Department of Entomology

Michigan State University

East Lansing, MI 48824


Introduction

The emerald ash borer (Agrilus planipennis) is an exotic, invasive insect that has infested and killed an estimated 8-10 million ash trees since its accidental importation from Asia. The infestation is now established across more than 5,000 square miles in 13 counties in southeast Michigan, as well as in neighboring Essex County, Ontario. Isolated, localized infestations, termed “outliers”, exist elsewhere in Michigan, northwest Ohio, and northeast Indiana. While the emerald ash borer infestation is regional in scope, its impact on the nursery industry has been felt nationwide, as growers across the country report a sharp decline in demand for ash trees.

All major eastern North American ash species have been killed by emerald ash borer, which infests trees ranging in size from ½ inch caliper nursery stock to fully mature trees in forests. While most native borers colonize only weakened trees, emerald ash borer attacks healthy trees as well, making it especially devastating. If it is not contained and eradicated, the impact of emerald ash borer on ash in North America will be similar to that of chestnut blight and Dutch elm disease. These exotic pests devastated natural and urban forests in the 20th century.

However, an aggressive, coordinated containment and eradication program undertaken by federal, state, and Canadian agencies provides reason to be optimistic that North American ash trees can ultimately be spared the fate of elm and chestnut. The objective of this article is to provide some background on the current state of the infestation and an overview of the eradication program, while clarifying some misconceptions that appeared in the August 1, 2004 issue of American Nurseryman (“Michigan takes three-phase approach to fight EAB”). Two of us (McCullough and Herms) are members of the National Emerald Ash Borer Science Panel, and all three authors are heavily involved in emerald ash borer outreach and research, including projects directly relevant to the nursery and arboriculture industries.

Historical Background

Emerald ash borer was unknown in North America until June 2002, when it was determined to be the cause of unusually widespread ash mortality in southeast Michigan, and was discovered shortly thereafter just across the Detroit River in Windsor, Ontario. This insect is native to areas of Asia, including eastern Siberia, northeastern China, Mongolia, Japan, and Korea, where it occurs on several species of ash. It was probably imported into Michigan via infested ash crating or pallets, perhaps 10 to 15 years ago.

Emerald ash borer was first discovered in Ohio near Toledo in February 2003. Isolated infestations were subsequently found in four additional counties in northwest Ohio, as well as in suburban Columbus. In the spring of 2004, two additional outlier infestations were discovered in northeast Indiana. Contrary to the August 1st American Nurseryman article, no emerald ash borer infestations have been detected in Wisconsin.

Most of these outlier infestations have been linked to artificial spread of emerald ash borer from southeast Michigan through movement of infested ash nursery stock, logs, and firewood. This largely occurred before emerald ash borer was identified and state and federal quarantines were imposed. An infestation discovered in a Maryland nursery in August of 2003, however, resulted when a Michigan grower violated the quarantine and shipped infested ash trees. This resulted in stiff penalties for the grower that included substantial fines, restitution, and community service. Eradication programs were promptly implemented in Maryland and neighboring Virginia, which received some of the trees from Maryland. So far, no additional infestations have been discovered. Meanwhile, the infestations in Michigan, Ohio and Indiana already have, or soon will be, subject to the outlier eradication program described below.

Economic and Ecological Impact

The economic and ecological impacts of emerald ash borer have already been substantial, and will be staggering if the infestation continues to spread. Ash species inhabit a variety of soils and ecosystems, and are dominant throughout the forests of eastern North America. According to USDA Forest Service statistics, there are at least 700 million ash trees in Michigan forests and 3.8 billion in Ohio (including more than 70 million that exceed 5 inch DBH), with standing timber valued at more than $1 billion. Furthermore, ash has been one of the most important nursery and landscape species. According to the USDA, wholesale value of ash trees sold in the United States exceeded $31 million in 1998, a market that has been decimated since the discovery of emerald ash borer.

Emerald ash borer has already caused tens of millions of dollars of damage to Michigan landscapes, urban forests, and woodlots, and this cost is increasing at an exponential rate. The cost of removing dead and dying ash has overwhelmed municipal budgets in affected counties. A quarantine on ash timber and firewood has also had negative economic impacts on sawmills, tool handle factories, and firewood dealers in Michigan and Ohio.

Taxonomy and Biology

Taxonomically, emerald ash borer is a beetle (Coleoptera) belonging to the family known as metallic wood-borers (Buprestidae). Larvae of these beetles are known as flatheaded borers, deriving their common name from the larval stage, which appears to have a broadly flattened head (it is actually the thorax which mostly conceals the much smaller head). Emerald ash borer larvae are white with a long (about one inch when mature) narrow, segmented abdomen that is also flattened, which gives them the appearance of small tapeworms. Adults are elongate, 1/2 inch-long beetles with striking, metallic green coloration.

Emerald ash borer belongs to the same genus (Agrilus) as bronze birch borer (A. anxius) and twolined chestnut borer (A. bilineatus), both of which are native to North America. The biology of emerald ash borer is quite similar to its native relatives. Generally, there is one generation each year, although recent studies by Michigan State University researchers suggest that development may sometimes take longer in newly infested, healthy trees. Adult beetles emerge from infested ash trees in late May through early August, with emergence peaking in mid to late June. As adults emerge, they leave small (1/8 inch), distinctly D-shaped exit holes in the trunk and main branches. Adults may live 3-6 weeks and nibble on small patches of ash leaves during this period. Females generally produce about 50-80 reddish eggs, which are laid individually on the bark surface, or within bark cracks and crevices. When larvae hatch, they tunnel into the tree, where they feed on the phloem and outer sapwood, excavating S-shaped, serpentine galleries just under the bark. These galleries disrupt the flow of nutrients and water between the canopy and roots. This causes canopy thinning and branch dieback, and ultimately tree death. Larvae continue to feed through summer and into the fall. They overwinter in the outer bark or within the outer inch of sapwood. Pupation occurs in mid to late spring. Adults emerge soon thereafter to complete the typical one year cycle.

Host Plants and Impact

Ash species known to be infested in Michigan include green (Fraxinus pennsylvanica), white (F. americana), black (F. nigra), and blue ash (F. quadrangulata), as well as horticultural cultivars of these species. Only living trees are colonized. Emerald ash borer will not colonize a dead tree. In China, emerald ash borer colonizes the Asian ash species F. mandshurica (Manchurian ash) and F. chinensis. In Japan, species of Juglans (walnuts and bitternuts), Ulmus (elms), and Pterocarya (wingnuts) have also been recorded as hosts. However, emerald ash borer has not been well studied in Asia (a total of three published pages), and these host records may reflect the existence of subspecies or simply taxonomic confusion. Furthermore, host records for borers are notoriously unreliable, and often include tree species from which adults were collected, even when the larvae are not able to develop on those species. Research on host range and host preference is underway and preliminary results from Michigan State University studies strongly suggest that walnut and elm will not be viable hosts for emerald ash borer in North America. Studies are also underway to investigate the susceptibility of plants related to ash, such as lilacs and privet. To date, these species have not been observed to be infested, even when growing in close proximity to infested ash trees.
 
Looks like it's gonna be 3 parts.....
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Diagnosing Emerald Ash Borer: Signs and Symptoms

Infestations of emerald ash borer are usually difficult to detect until they become severe. Larvae are hidden under bark and adults may spend most of their time in the upper canopy. Research indicates that emerald ash borer usually colonizes the upper trunk area of large trees first, which makes it difficult to see any diagnostic signs or symptoms. In addition, symptoms of emerald ash borer infestation often resemble other causes of tree decline.

Symptoms that are usually associated with ash borer infestation include small, vertical splits in the bark that can sometimes be observed on large branches or on the trunk. These splits occur when callus tissue that forms around a larval gallery pushes the outer bark away from the sapwood. To confirm the presence of emerald ash borer, one can widen the splits to reveal larvae and galleries under the bark. Usually, larval galleries are distinctly S-shaped or serpentine, and are packed tightly with frass (mixture of sawdust and excrement). They are also visible on the inner surface of the outer bark when it is removed.

The presence of small, distinctly D-shaped exit holes in the trunk or scaffold branches is a good sign of infestation. As infestations progress, the canopy starts to thin and branch dieback may occur. Decline often accelerates rapidly at this point. When emerald ash borer populations are high, trees typically die within 2-4 years of infestation. Epicormic shoots often sprout from the main trunk of declining trees and root sprouts sometimes occur at base of dying trees. Woodpeckers are proving to be important predators of emerald ash borer. A noticeable increase in woodpecker activity on ash trees can provide an early indication of an infestation, especially during winter.

Green Industry Research

In Asia, emerald ash borer does not devastate its native hosts. Rather, reports indicate that outbreaks are relatively uncommon, isolated and associated with stress events such as drought. This suggests that Asian ashes may be generally resistant, and that emerald ash borer preferentially colonizes stressed trees. Thus, emerald ash borer seems to behave in Asia much as its close native relatives do in North America, including bronze birch borer and twolined chestnut borer, which also preferentially colonize stressed trees. Native trees may be more resistant to their native pests because of natural defenses that have evolved over eons. Hence, Asian ash trees may be a source of resistance genes.

Researchers at The Ohio State University (OSU) are collaborating with colleagues at Michigan State University (MSU) to investigate this possibility in a project funded in part by the Horticultural Research Institute and the USDA Agricultural Research Service (ARS) Floriculture and Nursery Research Initiative. An experimental ash planting was established in 2003 at the MSU Tollgate Education Center in Novi, Michigan (with trees donated by Bailey Nurseries, Inc., J. Frank Schmidt and Son Co., and Lake County Nursery, Inc.) to compare resistance of North American, European, and Asian ashes to EAB, identify mechanisms of resistance and susceptibility, and determine the effects of drought and other stressors on borer susceptibility. North American species being evaluated include important cultivars of white and green ash, as well as blue, black, and Oregon ash (F. latifolia). European species include European ash (F. excelsior ‘Aureafolia’), flowering ash (F. ornus), and Raywood ash (F. oxycarpa ‘Raywood’), while Asian species include Manchurian ash (F. mandshurica ‘Mancana’) and Chinese ash (F. chinensis). The plantation also includes Northern Treasure ash (F. x Northern Treasure), which is a hybrid between native black ash and Manchurian ash. The first year of results are consistent with the hypothesis that Manchurian ash is more resistant to emerald ash borer than are North American species.

Scientists from MSU and the USDA Forest Service are also studying the relative preference of emerald ash borer for native species of ash, including green, white, black and blue ash. Several lab and field tests have been initiated to compare the rate of borer attack, feeding and development, and the response of these species to emerald ash borer. Preliminary data from these studies suggest that green ash may be more preferred and attacked sooner or at higher densities than white ash, while blue ash may be least preferred. Black ash, which is especially common in wet, swampy areas in much of northern Michigan and Ontario, also appears to be quite suitable as a host. These studies, funded by the USDA ARS and USDA Forest Service, are also providing data that may be useful in developing lures and traps for adults.

Information about the relative resistance of North American ash species and identification of resistant ash genotypes will be critical for reforestation, as well as restoring market demand for ash in the nursery industry. Identification of resistance mechanisms and their relationship to whole tree physiology will facilitate screening, selection, and/or breeding of resistant trees, as well as cultural management of emerald ash borer in urban and natural forests.

In addition, we (and others) are involved in a number of studies focused on the role of insecticides for control of emerald ash borer, both as an eradication tool and for protecting landscape trees within the core infestation zone. These studies are designed to address (1) the relative effectiveness of various insecticides for controlling emerald ash borer adults and larvae, (2) optimal timing for application of soil injections, trunk injections, and bark/foliage sprays, and (3) residual effectiveness of insecticides over time.

Statements in the August 1st American Nurseryman article suggesting that researchers have “sidelined” the Green Industry are simply not correct. Results of insecticide research from 2003 were widely disseminated and used in 2004 by many tree care professionals within the Core infestation zone in southeastern Michigan to improve or enhance their ability to care for landscape trees. Scientists at MSU are also working with several arborists and landscapers, not only to document the success stories, but also to learn as much as possible from treated trees that did not survive. In addition, several research sites in Michigan have been designated for long-term evaluation of the ability of soil and trunk injected insecticides to protect trees.

Because of the nature of the current program to eradicate outlier infestations, insecticide treatments for emerald ash borer are not recommended in Ohio, Ontario, Indiana and other areas outside the core infestation zone. In these eradication zones, all ash trees will be removed if an infestation is detected in their vicinity, even if they have been treated with an insecticide (for the rationale behind this recommendation see the January 1, 2004 issue of American Nurseryman, “Hold off on treating your ash trees with insecticides – for now”).
 
The Plan to Eradicate Emerald Ash Borer: The Cooperative EAB Project

USDA APHIS (Animal and Plant Health Inspection Service), the USDA Forest Service, and the Canadian Food Inspection Agency (CFIA), in cooperation with state Departments of Agriculture and Natural Resources have joined forces to implement a long-term program to contain and eventually eradicate emerald ash borer from North America. The plan, which is in the early stages of implementation, is to (1) locate and promptly eradicate outlier infestations, (2) prevent establishment of new outlier infestations through aggressive enforcement of state and federal quarantines, and (3) contain, suppress and ultimately eradicate the core infestation. A key component of the eradication plan is an intensive monitoring program to evaluate the success of outlier eradication efforts, identify existing, low-density infestations that have so far escaped detection, and quickly detect new infestations.

Rapid elimination of outlier infestations before they expand and become entrenched is critical. To date, several outlier eradication programs have been implemented in Michigan, Ohio, Maryland and Virginia, resulting in the destruction of more than 100,000 ash trees. Eradication of outlier infestations involves removal of all visibly infested trees, as well as all other ash trees within a ½ mile radius of the visibly infested trees. Since infested trees do not show external signs or symptoms of attack during the first year, there is no way to determine which trees in the vicinity of infested trees were themselves infested. Consequently, it is necessary to cut even apparently healthy trees to destroy the insects lurking within before they can emerge, disperse and reproduce. Felled trees were chipped and incinerated at a co-generation power plant, and stumps were treated with herbicide to prevent sprouting.

Three major studies of Michigan outlier infestations in 2003 and 2004 provide a science-based rationale for the current eradication strategy. This research (conducted by scientists from MSU, USDA APHIS, USDA Forest Service, along with volunteers from several state agencies, Purdue University and OSU) involved felling and peeling bark from a large number of ash trees of all sizes occurring within ½ mile of a known point source – e.g. the infested firewood or nursery trees from which the infestation was known to originate. Intensive sampling showed that 80% of all larvae were in trees within 100 yards of the original point source. At one site, infested trees were found as far as 750 meters (nearly ½ mile) from the point source. But at the other two sites, all larvae were found within 0.38 miles of the point source. Therefore, the cutting of all ash trees within a ½ mile radius of visibly infested trees should eliminate the vast majority of insects in outlier infestations, if not the entire infestation. Treating infested trees with insecticides as an alternative to destroying them is not a viable option for eradication sites. While research has shown that preventive insecticide applications can effectively protect shade trees from emerald ash borer in the core infestation in southeast Michigan, no insecticide program has been effective enough for eradication purposes.

To ensure success, these outlier eradication sites are being monitored for at least three years after cutting to determine if there is a need to “mop up” any beetles that may have slipped the dragnet. While some people have called for even more aggressive action at outlier sites, this strategy is a workable compromise. Eradication is expensive and disruptive, and increasing the radius of the area that is cut means that an exponentially greater number of trees must be destroyed. For example, a circle with a radius of one mile occupies four times the acreage of a circle with a ½ mile radius. Consequently, it is less expensive and less destructive to monitor eradication sites intensively, and then implement a follow-up eradication program if necessary.

However, monitoring efforts have been complicated by research that indicates that emerald ash borer apparently does not produce the long-range pheromones that have been so useful in trapping other insect pests such as gypsy moth. Rather, monitoring is currently being conducted in Michigan, Ohio, and Indiana by means of an extensive grid of “trap trees,” which consist of a girdled green ash tree wrapped with a band of sticky tanglefoot or similar substance. Research conducted by MSU and USDA Forest Service scientists in 2003 showed that adult beetles were more strongly attracted to girdled trees than to unwounded trees, possibly due to host plant volatiles released into the air by the girdled trees. It should be emphasized that the extensive grid of trap trees is strictly a monitoring tool to assess the distribution of emerald ash borer and aid in detection of outlier populations, and is not intended as a control measure, as suggested in the August 1st American Nurseryman article.

There are so many infested trees in the core infestation zone in southeast Michigan and neighboring Essex County, Ontario that it is physically and economically impossible to remove them all or to treat them with insecticides. Scientists and regulatory officials have developed a plan to surround and contain the core infestation with a Reduced Ash Zone (RAZ) that will likely extend through central and southwest Michigan, and across northeastern Indiana and northwestern Ohio. The optimal location of the RAZ is being determined by analyzing a combination of aerial photos, land use data and ground surveys to estimate ash density and emerald ash borer distribution. The RAZ will be routed as much as possible through areas with naturally low densities of ash such as agricultural land, industrialized areas, and large bodies of water. Incentive-based programs and ash markets will be developed to encourage property owners to remove and sell ash trees of all sizes before they are killed by emerald ash borer or removed in an eradication action.

An aggressive emerald ash borer suppression program will occur just inside the RAZ to relieve pressure on the leading edge and minimize emerald ash borer breakouts. An intensive monitoring program within and beyond the periphery of the RAZ will be implemented to rapidly detect the spot infestations that will inevitably breach the RAZ so that they can be quickly extinguished. It is important to realize that all of the ash trees in the RAZ will be inevitably be killed, as will billions more, if emerald ash borer is allowed to spread unchecked across North America.

Preventing the artificial spread of emerald ash borer is another major component of the eradication plan. Accordingly, federal, state, and Canadian quarantines have been enacted to prohibit movement of firewood, ash nursery stock, logs, wood chips, and untreated lumber. In the August 1st American Nurseryman article, the quarantines were characterized as ineffectual, basically voluntary, with no effort to enforce them. On the other hand, Tom Harrison, the head of the Plant Pest Control Section of the Ohio Department of Agriculture paints a different picture, referring to the quarantines as “the most far-reaching and heavily enforced to date.”

Preventing the movement of firewood presents a particularly tough challenge that has been recognized by regulatory officials since day one. Many federal, state and provincial agencies, along with extension personnel at Michigan State, Ohio State, and Purdue Universities are assisting regulatory officials by actively spreading the word about the emerald ash borer and particularly the dangers posed by transporting firewood. A multi-media, multi-agency publicity campaign featuring television, radio, and newspaper ads, billboards, press releases, fliers, posters, and bulletins has been launched to inform people about the firewood quarantine. Highway signs warn motorists of substantial fines for moving firewood outside the quarantine zone. A stepped-up inspection and enforcement program will target violators at rest areas, along highways, and at campgrounds at critical times such as major holidays and during hunting season. Canadian officials have already begun ticketing violators at their camp sites. These and related outreach and enforcement efforts will continue and expand to minimize the artificial spread of emerald ash borer.

In Closing

Emerald ash borer has the potential to decimate ash throughout North America, but efforts to eradicate this invasive pest are now underway. Eradication is possible but will require considerable resources and political will. Even if these efforts are not successful, as some critics suggest, the Cooperative Eradication Project will dramatically slow the spread of the infestation, buying time needed for research advances on effective traps, biological controls, and host plant resistance and other strategies. The eradication program will require a long-term commitment of funds and effort. But these costs will be miniscule compared to the devastating economic and ecological impacts of emerald ash borer if it is allowed to spread unchecked throughout North America. It is a battle that must be fought.
 
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