Ash borer not alone in threatening shade trees

5/3/2004
BY TOM HENRY
BLADE STAFF WRITER
  • Ash-borer-not-alone-in-threatening-shade-trees

    Fulton Street, facing Bancroft Street, has been replanted to try to restore the stately glory provided by elm trees lost to disease.

    Hires / Blade

  • Many Americans celebrated Arbor Day for the 119th time this year, unaware that the man who founded the event was a transplanted Detroit-area resident upset over the lack of trees in Nebraska.

    There's irony to that fact, for many tree-lined streets that Arbor Day founder J. Sterling Morton enjoyed while he lived in the Detroit area are now under threat.

    Although the Detroit area is not as barren as Nebraska was when Mr. Morton founded Arbor Day in 1885, 6 million ash trees in southeastern Michigan are dead, dying, or being cut down because of a devastating foreign pest, the emerald ash borer.

    Drastic as that sounds, it could be only the beginning of an altered landscape for Michigan, Ohio, and Indiana.

    Officials are so worried about the havoc the bug could cause that they have begun discussing the possibility of cutting a huge swath across those states.

    Canada clear-cut 84,000 ash trees across Ontario's southwestern peninsula a few weeks ago.

    A semicircle running south from Michigan into northwestern Ohio and northeastern Indiana would involve tens of thousands, if not millions of ash trees, creating a firebreak-like barrier up to 6 miles wide, said Sharon Lucik, spokesman for the U.S. Animal Plant and Health Inspection Service in Brighton, Mich.

    The cost could be millions of dollars and the project could take eight years, said Bob Waltz, an Indiana Department of Natural Resources entomologist.

    In 1962, diseased elms on Fulton Street were removed, part of a city-wide project to remove infected trees from Toledo streets.
    In 1962, diseased elms on Fulton Street were removed, part of a city-wide project to remove infected trees from Toledo streets.

    With billions of trees, this region doesn't appear to be in any imminent danger of becoming treeless.

    Yet forestry experts and nursery owners admit the emerald ash borer is one of many threats causing anxiety over the fate of some species of trees that provide the region with shade and beauty, and even help cleanse the air.

    "We are now seeing an array of threats to Ohio's forests that are unprecedented," said Tom Harrison, a veteran plant pathologist for the Ohio Department of Agriculture who's studied such issues for more than two decades.

    Besides the emerald ash borer, there are other threats to our trees, some already in this region and some feared to be on their way. Among them: Asian longhorn beetles, gypsy moths, beech scale insects, hemlock woolly adelgid, and sudden oak death fungus.

    The fungus, first noticed in central California oaks in 1995, may have been spread by a Los Angeles nursery. A shipment to the Cincinnati area is under review by investigators.

    "I think we've had more exotic pest flare-ups in the past four to five years than we have had in the past 20 years combined," Mr. Harrison said.

    Contributing to the declines are developers who clear land for more housing subdivisions and retail plazas. Maintenance activities by FirstEnergy Corp. and other utilities to trim back trees from power lines to prevent blackouts are factors as well. Many trees also are felled by oil companies to maintain an aerial view of their pipelines.

    Remember Dutch elm disease?

    It began in Cleveland in 1930, when the disease started its stranglehold on the American elm tree, one of the nation's most popular shade trees for residential neighborhoods. By the 1960s, elms were struggling to survive.

    Most people today don't remember when the American chestnut tree was the dominant hardwood species in the eastern United States, including Ohio, where it once was the state's most common tree. An exotic fungal disease known as chestnut blight wiped out the species by the 1950s.

    Years later, butternut trees - a relative of the black walnut highly valued for furniture - were decimated from much of the continent by another fungus.

    The U.S. Department of Agriculture's Forest Service has described the loss of those species as "three American tragedies," each caused by fungal diseases from other continents.

    Today, few state or federal officials from this part of North America spare any adjectives when discussing the potential impact of the tiny Asian beetle.

    "The emerald ash borer is the worst of the bunch, because it's so devastating to its host tree," said Mr. Harrison, who heads up Ohio's emerald ash borer task force.

    Michigan Department of Agriculture Director Dan Wyant even went so far as to formally declare the bug a menace to society.

    "It's hard to survey or detect," Mr. Harrison said, "and you must take draconian measures to get rid of it when you find it."

    Those draconian measures include cutting down more than 20,000 ash trees in Ohio this year alone, including about 15,000 in northeast Columbus, one of several pockets of the Buckeye State where the beetle has been detected.

    About 1,500 trees were targeted for destruction in the vicinity of Hicksville, Ohio, and an additional 450 in the Perrysburg/Rossford area. Hundreds were destroyed last year in western Lucas County, near Whitehouse, and hundreds more will be coming down as soon as this week near Ohio's latest confirmed site, south of Toledo Express Airport.

    That's because with no safe, foolproof pesticide developed to kill this bug, protocol calls for destroying all ash trees within at least a half-mile radius of known infested sites. The idea is create a gap big enough to cut the beetle off from its food source. Pesticides are applied to trees just beyond that perimeter as a backup.

    Ohio's figures, however, pale in comparison to what's been going on in Michigan, where 6 million ash trees have died or are being cut down.

    On Friday, Governor Jennifer Granholm asked President Bush to declare Michigan a major disaster area to help make the state eligible for more federal funding for eradication efforts. The cost of addressing the problem in Michigan is estimated to be greater than $163 million. The state has received $29 million from the federal government so far.

    Michigan has quarantined a 13-county area in the southeastern part of the state seen by experts as the epicenter of North America's infestation. The bug was discovered in that part of Michigan in 2002, but officials now realize it may have been there for as long as a decade. It has since spread to other parts of Michigan.

    Across the Detroit River, at least 84,000 ash trees in Ontario's southwestern peninsula from Lake St. Clair to Lake Erie - a swath of land 6.2 miles wide and 18.6 miles long - were clear-cut this year. That $12 million project was an attempt to prevent the beetle from spreading to other parts of Canada.

    Emerald ash borers also have been found in Indiana, Maryland, and Virginia.

    In the case of Maryland and Virginia, the infestation was blamed on a Michigan nursery owner who ignored the state's quarantine and shipped infested ash trees there. Stuart Leve pleaded no contest in November to 123 counts of violating Michigan's emerald ash borer quarantine and plant health laws. He was sentenced Dec. 10 by District Court Judge Brian MacKenzie in Novi, Mich., to the maximum sentence of $12,300 - $100 for each count - and was ordered to pay $16,000 in restitution to a Maryland nursery that had unknowingly purchased infested trees from him.

    The judge left open the possibility of ordering Mr. Leve to pay thousands more in restitution to Maryland and Virginia for their expenses, officials said.

    Drew Todd, state urban forestry coordinator for the Ohio Department of Natural Resources, said the emerald ash borer has the potential of being every bit as devastating as Dutch elm disease.

    "From a potential damage standpoint, it is very similar," he said. "It has the potential to alter the composition [of the landscape] drastically."

    Mr. Harrison agreed. "Dutch elm disease didn't kill all the elms in a year or two. Whether or not the current containment efforts [for the emerald ash borer] work - that's still in the cards."

    Many of the problems faced by trees in the Great Lakes region parallel threats that have emerged in the world's largest collection of fresh surface water: The onslaught of exotic species.

    Invasive species have hitched rides in the wooden shipping crates and ballast water of ocean-going ships, gotten off in the vicinity of port cities such as Detroit and Toledo, then blitzed the North America ecology with a set of problems many scientists here have never seen before.

    Invariably, the destruction has created new learning curves - but it's often been a game of catch-up, because officials admittedly haven't known what to predict whether it's on the land or beneath the water.

    Scientists acknowledge the problem will get worse because of emerging global trade markets.

    Increased trade with Asia has the potential of causing more ecological threats, because Asia's climate has more in common with North America's than Europe's, experts said.

    "It's inevitable that we're going to have invasives that get established and disrupt the ecology," said Dan Herms of the Ohio Agricultural Research and Development Center in Wooster, Ohio. Mr. Todd agreed. "As the world economy evolves and the ease of shipping increases, there are more and more opportunities for these things to happen," he said.

    They and others are looking beyond the traditional ivory towers of a major university for help: the U.S. Department of Homeland Security.

    Officials believe the attempt to slam the door on exotics will benefit greatly from the government's enhanced efforts to keep out terrorists. That's because security includes better detection of chemical agents, not just people. Invariably, that should lead to better detection of biological pests foreign to North America, they said.

    "There's a lot more emphasis being paid to the ports, not just in looking for terrorists but also for pests," Mr. Harrison said.

    The evolving changes are hard on people like Tom Oberhouse, who owns North Branch Nursery, Inc., in Pemberville, one of northwest Ohio's largest tree farms. Although not in a quarantined area, he said he's all but given up on the ash making a comeback as a landscaping tree.

    White ash is Ohio's third-most common tree, with an estimated 3.8 billion statewide. They have contributed millions of dollars to the economies of Michigan and Ohio in nursery sales because of their popularity as a landscaping tree.

    They've also contributed millions of dollars because of their role in manufacturing. Ash is used to make products ranging from wood flooring to baseball bats; in Ohio, the manufacture of ash-made tool handles is one of the state's larger businesses.

    "The emerald ash borer is kind of all-consuming at this point," Mr. Oberhouse said.

    Mr. Oberhouse said the bug's threat is the worst he can recall in his 24 years in the nursery industry. He said he is hopeful a pesticide will be developed, but doesn't see that reversing the damage to nurseries.

    "Most people don't want a tree they have to put pesticides on every year," he said.

    In the aftermath of Dutch elm disease, ash trees were seen as a shade-tree replacement for the loss of elms. Now, hybrid elms that are resistant to Dutch elm disease are displacing ash as landscaping trees, Mr. Oberhouse said.

    Call it another sign of homogenization among continents: Scientists are in the early stages of coming up with a hybrid ash that would be resistant to the emerald ash borer. They're studying ash trees in Asia that can tolerate the bug. A collaborative effort among Michigan, Ohio and federal scientists is underway at the Michigan State University Tollgate Research and Education Farm near Novi, Mich., about an hour north of Toledo. On April 24, officials planted 800 trees, including two species of Asian ash.

    "Two years ago, none of this seemed real significant to me," confessed Mr. Herms, an Ohio researcher involved in the effort. He now is confident that ash hybrids will be developed that are resistant to the emerald ash borer.

    Years ago, a knee-jerk reaction to attacking tree problems such as the emerald ash borer might simply have been mass fumigation with chemicals.

    In the late 1950s, DDT was used to curb Dutch elm disease. Much of it was surplus chemical left over from World War II, when it was used to help the military combat malaria or yellow fever.

    After studying bird deaths on the Michigan State University campus that had been linked to DDT, however, researchers eventually concluded that robins were poisoned by eating DDT-contaminated earthworms.

    DDT was later blamed for decimating America's bald eagle population because it made eagle eggshells thin and vulnerable.

    In 1962, Rachel Carson published her landmark book, Silent Spring. The book has connections to Dutch elm disease, in the sense that it begins with a description of a strikingly eerie silence that could have befallen the nation if robins and other birds continued to die from DDT

    Ms. Carson, a former aquatic biologist for the U.S. Fish and Wildlife Service, was lauded by Time magazine as one of the most influential people of the 20th Century for awakening the scientific community to the dangers of chemical overexposure.

    Since then, the chemical industry's products have come under closer scrutiny and a new generation of scientists has grown up looking for links between excessive use of chemicals and cancer, with the latest research evolving toward birth defects, reproduction problems, and child development problems.

    "Silent Spring still has an impact on what our scientists are doing and how they're doing it," Mr. Todd said.

    Looking for solutions other than pesticides "reduces your arsenal to some degree and rightfully so," Mr. Harrison said, "because there are some tools you use that are worse than the actual pest."

    Cutting down trees is an alternative. Considering the outcry that chopping down a property owner's trees can generate, officials say they appreciate the public's sacrifice to accept the destruction being done in some areas in an effort to halt the emerald ash borer's spread.

    "This is a very drastic thing for us," Mr. Harrison said. "We don't take pleasure in taking these trees down. It strikes a little bit of emotion in you that you didn't know you had. It's hard."

    Contact Tom Henry at: thenry@theblade.com or 419-724-6079.