The Silent Killers

The state’s ill-conceived effort to expunge the irrepressible emerald ash borer has wasted precious Michigan tax dollars, cost businesses and homeowners millions of dollars in damages, and led to the destruction of billions of North American ash trees.
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An adult beetle believed to have arrived from China in shipping crates; a once-thriving ash tree decimated by the ash borer; a larva creating tunnels of destruction; and a side view of the adult beetle. While the emerald ash borer has destroyed billions of ash trees in the Midwest, a new treatment plan and strict ordinances could limit further damage. Photograph by David Cappaert/bugwood.org

In the closing minutes of Clint Eastwood’s hit movie Gran Torino, the film’s credits scroll across the screen over a striking panoramic view — Lake Shore Drive going east through Grosse Pointe Farms.

While the picturesque view of Lake St. Clair’s shoreline was undoubtedly Eastwood’s focus, the cameras also showed a stand of graceful, healthy ash trees lining the boulevard, a sight that, in years to come, might exist only on film, as the popular landscape tree faces extinction in North America. In fact, thanks to a misguided government rescue plan, the devastation of billions of stately ash trees has already cost businesses and residents millions of dollars in damages, with more on the way.

Several years before it was discovered in 2002, the tiny — yet prolific — green beetle dubbed “the emerald ash borer” began relentlessly attacking and killing ash trees, first in Canton Township, then across western Wayne County, and now in every county in Michigan’s Lower Peninsula.

Officials believe that the lethal pest hitchhiked into the country, undetected, on packing crates from China. Compounding the problem is southeastern Michigan’s status as a major player in world trade. Over the past seven years, even as federal and state officials allocated more than $50 million of taxpayer money trying to stop it, the ash borer has been like a plague, burrowing its way across Michigan and leaving scores of ravaged ash trees in its wake.

What the government got in return for the $50 million hasn’t been encouraging. In Michigan alone, more than 30 million trees have perished, and the borer is showing signs of expanding into the Upper Peninsula. Overall, the emerald ash borer has killed an estimated 50 billion ash trees in at least nine other Great Lakes and Midwestern states, as well as in the Canadian province of Ontario. The U.S. Department of Agriculture estimates this has all cost the lumber industry some $60 billion.

Because of its leafy qualities and its hardy resistance to disease, ash was the tree of choice in recent decades for municipalities and landscapers across the country who were eager to replace another devastated tree species — the Dutch elm. In the middle of the 20th century, millions of elm trees were wiped out by a fungal disease spread by the dreaded elm-bark beetle. Scientists have yet to develop an effective cure for Dutch elm disease, but they have created hybrid trees that are resistant to it, although they don’t match the majesty of the original.

While the ash was initially a popular replacement for the Dutch elm, it, too, has succumbed to an outside predator. In fact, the emerald ash borer has proved to be such a virulent killer that businesses, homeowners, and state and local governments could face another $7 billion in costs in the next 25 years removing and replacing ash trees, according to federal estimates. According to the USDA, ash trees represent a $100 million to $140 million annual market for nurseries nationwide.

Even the Great Lakes haven’t proved an effective barrier to the borer. Last year, it was found in Wisconsin and around Chicago. Ash tree attacks have also been reported in Ohio, Indiana, Pennsylvania, Maryland, Missouri, Virginia, and West Virginia. The borer’s invasion into Windsor has already spread east to Ottawa and Montreal, near the U.S. border, where it threatens New York and Vermont. The prognosis for ash trees is grave enough to prompt the USDA to sponsor a program in East Lansing where seeds of mature stands are being collected and stored for the future.

 The ash tree devastation has contributed to price hikes for consumer items such as tools, hunting equipment, and electric-guitar bodies, not to mention millions of replacement trees in office parks, residential neighborhoods, college campuses, and urban squares. Even Major League Baseball is being affected. Louisville Slugger, the official supplier of bats to our national pastime, is closely monitoring the borer. In the 1950s, the company locked up hundreds of acres of ash-populated woodlands in Pennsylvania. As it stands, around 80 percent of the 1.6 million bats used by major-league players each year are ash — or, more specifically, old white ash.

Some Pennsylvania white-ash vendors reportedly cut down their trees early, to stockpile the wood for future bat-making.

Authorities say that campers who take firewood from home, RV owners who move infested firewood, and nurseries who exported ash stock to other states (it’s now prohibited by law) are among the main culprits who inadvertently contributed to the ash borer’s devastation.

Each fall, the dreaded beetles begin a one-year cycle from the time eggs are deposited on the bark of trees. Their eggs burrow into the bark and develop into tiny, tunnel-carving larvae that effectively cut off the flow of water and nutrients from the tree trunks. Adult borers emerge in June, and before dying in three weeks, the female can lay nearly 100 eggs.

In recent years, local arborists have had varying success saving individual ash trees, such as those on Lake Shore Drive in Grosse Pointe Farms, by injecting them with an insecticide that kills the larvae. Meanwhile, the development of a spray to control the ash borer has been a priority for scientists at Michigan State University.

Some experts, however, believe that by the time the borer was identified as the culprit by MSU plant pathologist Dr. David L. Roberts in 2002, the bug had such a head start that it may have been too late to save the ash population.

As trees began to die in alarming numbers at the start of the decade, scientists, including some at MSU, erroneously blamed the cause on a disease called ash yellows. Others said it was the work of a common native insect, the two-line chestnut borer. By the time Roberts settled that debate, the emerald ash borer was established in more than half a dozen counties in southeast Michigan.

With no history of the insect to guide them, local response by the Michigan Department of Agriculture has been an effort of trial and, mostly, error. Before turning to biological warfare, state officials launched a three-year program in 2003 to snuff out the emerald ash borer. Records show that before abandoning the program, the Department of Agriculture spent $9.3 million.

Some critics believe that the program not only failed, but that it allowed the emerald ash borer a passage out of southeast Michigan.

Under the “cut and chip” program, as it was called, paid for by the USDA but run by the state Department of Agriculture, the public, local governments, and home and business owners were urged to cut down healthy and infected ash trees, and dump the lumber in four official collection yards around the region. The wood would then be reduced to 1-inch chips and trucked to an electric power plant in Flint for disposal in the facility’s wood-burning incinerator.

MSU scientists and the agriculture department officials were convinced that grinding ash wood into 1-inch chips would kill the emerald ash borer. At the time, 13 counties around metro Detroit were placed under a quarantine that prohibited moving ash wood out of those areas. But before the first tree was cut down, the program stumbled.

First, officials at the state Department of Management and Budget, who handled the contracting for the work, inexplicably awarded the initial multimillion-dollar, wood-grinding contract to a Philadelphia-based national tree-trimming company. At the time, the company did not own a single grinder and had no experience in the business.

In doing so, officials passed over Environmental Wood Solutions Inc. in Lake Orion, a top-flight grinding company in the Midwest. In fact, the company’s experts had been consulting with state officials as they were formulating the wood-grinding operation.

Larry Mullins, president and owner of Environmental Wood Solutions, told state officials their plan wouldn’t work because he doubted the grinding would kill the tiny, but resilient, emerald ash borer. “I’ve seen a field mouse come out unscathed from a 1,000-horsepower grinder,” he says. “So it made sense that something as small as the emerald ash borer would survive.”

Mullins also warned that trucking chips out of the quarantined area to Flint would expose other communities along the way. Grinding the wood into mulch and dumping it into local landfills where it would decompose was a better approach, he suggested.

But Mullins’ advice was ignored. The Philly-based company won the permanent grinding contract using leased machinery, and company employees failed to grind 40 tons of ash per hour as specified in the test program. Mullins, on the other hand, had massive grinders — four that cost a combined $8 million, including one that spews wood chips at the rate of 120 tons per hour.

Instead of paying the advertised price of $387,464 for the pilot program, the state wound up paying the Philadelphia group $1.7 million after granting a 180-day extension to complete the pilot. After the program went into effect, millions of tons of wood chips were hauled to the Flint facility. Mullins’ prediction, unfortunately, came true.

Before the program got underway, state officials reassured their Genesee County counterparts that the process was safe. But within months of the first chips arriving at the Flint power plant, ash trees in the area began to show the telltale signs of ash-borer attacks. Eventually, they all died, and the county was added to the quarantine list.

In 2005, two years after the cut-and-chip program began, Roberts conducted an experiment at Environmental Solutions by grinding ash logs in one of the company’s most powerful grinders. “We found three live insects surviving in 10 pounds of chips,” he says. “And you can extrapolate, from that, how [many there are] in a million pounds.”

Mullins, who’s still bitter about his experience with state officials, says that everyone involved in the cut-and-chip program made out well except the taxpayer. “An out-of-state company made millions grinding wood, the power plant got all that fuel for free, truck drivers got paid, the state even paid for industrial wood waste dumped in those yards,” he says. “As far as I can see, all the state did was promote the spread of it by hauling the chips out of the quarantine area.”

Ken Rauscher, the state’s point man on the emerald ash borer, acknowledges that while the cut-and-chip program didn’t stop the bug, the collection yards protected the public by giving residents a place to dispose of dead trees that would’ve otherwise become hazards susceptible to wind and ice storms. He adds that the lack of any history with the emerald ash borer severely hampered officials, who were under pressure to take action.

“We started from scratch in 2002, with little knowledge of the pest and not a lot of knowledge about where it was in the state,” says Rauscher, director of the division of Pesticide and Plant Pest Management at the Michigan Department of Agriculture. “We knew what appeared to be the epicenter, based on dead trees. We didn’t know, for instance, how far it reached from there.”

Rauscher says the state isn’t giving up on the remaining ash trees in the mitten. Last November, agriculture department officials expanded the quarantine to include the entire Lower Peninsula. “I think there’s been a recognition that we weren’t going to eradicate the emerald ash borer,” he says. “As you spend three or four years in the program, you begin to realize we have a number of scattered infestations around the Lower Peninsula.”

Rauscher says the agriculture department’s main focus now is on education and outreach, although the emerald-ash-borer budget has been scaled back to $1 million per year. The money pays for enforcement of the quarantines in the lower and upper peninsulas, and for the process of certifying lumber, firewood, or other wood material shipped out of state. “Education and outreach is a big chunk of it,” he says, “and what we don’t do ourselves, we contract it out to MSU.”

An early misconception by the state was that the emerald ash borer was immune to any insecticide. The public was warned that treating ash trees to ward off attacks was a waste of time and money.

Longtime arborist Susan Shock took another approach. She figured early on that the insect, like any other borer, would be most vulnerable in the early larva stage. She deduced that timely injections during the incubation period in late spring would kill the larvae before adult insects could emerge from the trees.

“I had to look beyond the state’s discouragement and educate the public,” Shock says. “I said, ‘Yes, there’s nothing out there specifically for emerald ash borer, but in the meantime, let’s just go after it with what we use on similar insects like the bronze birch borer, and let’s not wait for an emerald ash borer label.’”

Shock used a small injection system called the Wedgle (which requires no drilling) to pump a powerful insecticide — Imidacloprid — in a line around the base of each tree. The Wedgle seals the tiny holes with a rubber plug to keep air or bacteria out as the insecticide flows up through the tree’s vascular system. For trees showing signs of stress, she fertilized the root system with the insecticide. Costing between $6 and $10 per shot, treatment for a 20-inch trunk comes to roughly $200.

“We’re now treating 600 trees in Grosse Pointe Farms, and we’ve lost only a handful,” Shock says. “Some were killed by some other insects or were taken down for construction or renovation, but we didn’t lose them to the emerald ash borer.”

Grosse Pointe Farms officials say the $25,000 treatment bill was a better investment than the estimated $600,000 that it would take to cut trees down and the years it would take to grow replacements.

In 2002, Shock also began applying the same treatments to dozens of towering older ash trees on the grand lawn of the 86-acre Edsel & Eleanor Ford House on Lake Shore Drive, where the trees were first planted in the 1920s.

“We haven’t lost any,” Shock says, “and we’re up to 83 trees under treatment.” Overall, Shock has successfully treated 1,800 ash trees in the region. Early intervention augurs well, she says, adding that homeowners should be prepared to treat trees every year for an indefinite period until another solution emerges.

Another local arborist with a successful track record of saving ash trees is Wayne White, of Emerald Tree Care in White Lake. Using the same process Shock employs, White has kept dozens of ash trees flourishing around the Somerset Collection in Troy, and has sustained rows of ash along the entrance into Oakland County International Airport. White was recently hired to treat trees for municipalities in Indiana and Wisconsin.

Last year, MSU researchers and the Environmental Protection Agency gave the green light to a new insecticide developed by a Swiss agrochemical company and a Massachusetts-based firm called Arborjet. The manufacturers say the product, Tree-äge, offers two years of protection after it’s injected into an ash tree.

There are other success stories, as well. On Harsens Island, 71-year-old John Horvath has been successfully treating 80 trees himself on his farm since he blocked state officials from cutting them down four years ago.

In March of 2005, state officials found the emerald ash borer in a trap tree that scientists had rigged to detect the presence of the insect on the island. The trap tree was 200 yards from Horvath’s ash-covered property. Using a state law that gives officials the power to take action to stop the spread of parasites, public workers showed up with a court order to cut down all of his healthy ash trees.

Horvath, a staunch property-rights advocate, blocked the entrance to his property by parking a large bulldozer across his roadway. The matter wound up in court, and Horvath saved his trees when a judge agreed to let him treat them.

Now the latest hope to corral the emerald ash borer rides on three species of tiny microscopic-sized wasps that have no stings. The wasps, which were imported from Asia, are being bred in mass quantities at a USDA facility in Brighton.

Scientists have spent five years working with the wasps in laboratories, making sure they’re clean of other parasites and that they’re selective in attacking only emerald ash borers. The wasps have been released in a few trials, and scientists will decide later this year whether to release them in Michigan and elsewhere. If they do, the wasps must be produced in large enough quantities that enough of them survive. The budget for the two-year program is $1.6 million.

“We’re optimistic that this is the best approach so far to controlling [it],” says Rauscher, director of the state’s previous unsuccessful emerald-ash-borer eradication program.

Roberts, however, isn’t convinced the wasps will do the trick. He points out that the emerald ash borer is not a serious problem in Asia, and he believes the natural resistance of Chinese ash trees to boring insects — not the presence of the wasps — is what protects those trees.

“The insect and [its] ash species have evolved together over thousands of years,” Roberts says. “Obviously, these predator parasites did not eradicate the insect over there.”

An experiment Roberts conducted supports his skepticism, he says. “We brought some of the Chinese ash trees to Novi at the Michigan State University Extension and planted them there among our native ash trees. While the native ash trees were attacked, the Chinese ash demonstrated they were already resistant or tolerant to this insect, and [they weren’t] killed by the emerald ash borer.”

Roberts is also dubious about introducing a new pest into the environment. “As a scientist, I’m very concerned about introducing new organisms — whatever they are — without extremely careful long-term impact studies,” he says.

Rauscher, however, believes those concerns have been addressed.

“‘Are you introducing something worse than the critter you’re trying to control?’ is a good question,” he says. “That’s not really the case here, and that’s the reason for the selectivity testing — to make sure [the wasps] only attack the critter you’re trying to control.”

While the state no longer discourages treatment of individual ash trees, it doesn’t suggest treating trees to save them, either.

“We have not promoted a program of trying to save ash,” Rauscher says. “What we have done is simply say to people that there are a couple of products out there that may be effective, and you’re free to use them with the recognition that there’s still a tremendous amount of emerald ash borer out there. If you have a specimen tree or trees that you really need to keep, you can try to treat them.”