An all-out effort to slow a green menace

February 18
The Kansas City Star

Eight hundred mature shade trees line the streets and common areas of the Timber’s Edge subdivision in south Overland Park. Sadly, every last one of them is an ash — and a potential goner now that the emerald ash borer has come to town.

“It’s just got me scared to death,” said Larry Myer, homeowners association president. “You get rid of the trees and suddenly the neighborhood doesn’t look so good.”

This entire region won’t look so good if the borer, a metallic green beetle from China, takes the toll experts fear it will. Millions of ash trees in this area could die, so federal, state and local authorities are preparing an all-out effort this spring to beat back the pest as best they can.

They’ll set out hundreds of traps, enforce quarantines and perhaps even employ parasitic wasps to hold off the scourge.

Yet ultimately it could be a losing battle for all but those who invest in expensive treatment programs to keep their trees alive.

“As far as insect problems,” Kansas City forester Kevin Lapointe said, “it’s probably the worst we’ve ever seen.”

Unless injected, sprayed or doused with insecticides that, depending on the size of the trees, can cost as much as several hundred dollars per treatment, every ash tree east of the Rockies is in danger.

Since arriving more than a decade ago in the Detroit area as a stowaway on packing material, the beetle has killed tens of millions of native ash trees in North America — 40 million in Michigan alone by some non-official estimates.

Now in danger are the 4.6 million ash trees in the Greater Kansas City metro area, officials say, setting the stage for an ecological disaster not seen since Dutch elm disease swept through a half-century ago.

“Left unchecked, it will take them all down,” Kansas City parks superintendent Forest Decker told the City Council recently.

The toll could be high because not every homeowner, neighborhood association or municipality with ash trees will take on the expense to fend off “the green menace,” as the U.S. Department of Agriculture has dubbed the bug. The Jackson County parks department, for instance, has already decided to let the critters have their way with an unknown number of ash trees on 21,000 acres of park land.

“There’s no plan to treat,” said biologist Belinda Thomes.

But not everyone’s given up the fight before it’s even started. Since confirmation last summer of the borer’s arrival in Platte and Wyandotte counties, authorities have devised strategies to contain the threat as long as possible.

The overarching theme: educate the public so that private and public property owners who do want to save their trees will have time to prepare. Treating smaller trees doesn’t have to be expensive, while the higher cost of treating large ones is still far less than paying to have a dead tree removed, local foresters and arborists say.

The public relations effort also highlights the continuing quarantine with fines up to $250,000 to prevent the insect from hitching rides on firewood and storm debris from Clay, Platte and Wyandotte counties.

In addition, war plans are being drawn. While mostly a defensive action, there’s an element of offense to it.

To monitor the enemy in both Missouri and Kansas, the USDA and the states will hang hundreds of traps in both states this spring. The three-sided, three-foot-long boxes are called “Barney traps” because they are the same color as the TV dinosaur.

Emerald ash borers, scientists have learned, are drawn to that particular shade of purple. (And new research at Penn State shows that fake females can lure males into traps.)

State and federal entomologists will also track and contain the bugs in other ways. Because the borers favor sick old trees over healthy ones in middle age, Kansas City and other local governments plan to cut down thousands of sick or weak trees that are most likely to attract the bugs first.

Other older trees will have their bark torn from them this spring, serving as bait to draw borers away from younger trees. Then come August, those trap trees and the larvae inside them will be removed and destroyed.

At some point, even an offensive strategy could kick in. Three species of parasitic wasps (natural foes of the emerald ash borer in Asia) were deployed in the Ozarks last year, slowing the spread of the beetle by laying wasp eggs in the eggs and larvae of emerald ash borers.

Still, those wasps are more of a speed bump than a silver bullet, killing no more than 7 to 10 percent of the developing ash borers in a given area.

Which pretty much sums up the conflict ahead. We may win some battles, but the emerald ash borers had the war won the moment they hit town.

“The goal is not to stop this, because we’re not going to,” Lapointe said. “The goal is to slow it down so it’s not catastrophic environmentally and financially.”

‘It’s scary’

There hasn’t been a threat as wide and deadly as the emerald ash borer since Dutch elm disease wiped out 3 billion trees nationwide in the years after World War II.

The emerald ash borer could cause an even higher death toll: 9 billion ash trees.

Since the pest’s discovery in the Detroit area in 2002, its range has expanded to 18 states.

Confirmation of its arrival in the metro area came last summer, when ash trees showing evidence of infestation were discovered in Platte and Wyandotte counties. So far there has been no sign of infestation south of the river.

“Though, quite frankly, we don’t take a great deal of comfort in that,” said Mike Brown at the federal Animal and Plant Health Inspection Service office for Missouri.

Brown and others suspect that the emerald ash borer has been in Kansas City for some time and is already infesting ash trees. We just haven’t noticed the tell-tale signs, including die-back in the crown and D-shaped exit holes in the bark when larvae fully mature and fly away.

Even so, just to be on the safe side, Kansas City is acting as if the river remains a boundary and is building a dump site for storm-damaged limbs and other debris in the Northland.

Ash is one of the most widely planted trees in the metro area. For instance, nearly a quarter of all the street trees in Overland Park are ash, according to city forester Sarah Patterson.

“Some neighborhoods are totally ash,” she said.

Lapointe said Kansas City is in danger of losing up to 10 percent of all the trees within the city limits from emerald ash borer, 400,000 by some estimates.

Some of Kansas City most prominent boulevards have nothing but ash trees along both sides. Ward Parkway south of 55th Street is pretty much all ash trees for several blocks and then again south of 79th Street.

There are ash trees up and down the Paseo, too. Up to 50 of the weakest will be cut down beginning next week.

But ash trees are even more numerous on private property, owing to their reputation for being hardy and attractive.

“You go to almost any development in the city,” says Lapointe, “and it’s almost all ash trees. It’s scary.”

City officials don’t have the power or the resources to protect the trees on private property from borer infestation. But the parks and public works departments have hatched a plan to deal with trees on city property: Spend $9.5 million over the next nine years to treat the 14,000 ash trees along city streets and boulevards with insecticide, while removing and replacing 6,000 others that probably aren’t worth saving.

Treat or not?

Not every local government is as far along as Kansas City, but Brown at the federal inspection service is not so worried about the government response.

“The most difficult part,” he said, “is the homeowner part.”

The average person doesn’t pay all that much attention to the trees in the yard. Ask homeowners if there is an ash out back and half of them might not even know.

So identification is the first step, Lapointe said. The second is deciding what to do next.

The rule of thumb is to consider preventative treatments when the beetles are found within 15 miles of your ash tree, which for many in the metro area is now.

For those who are willing to make the investment, there are three methods.

Emerald ash borers kill trees by first flying into the canopy and laying their eggs in bark crevices. When hatched, the larvae drill through the bark and tunnel to the underlying phloem, chewing on the tissue that carries nutrients through the tree.

Within a few years, the tree’s vascular system is damaged to the point that the limbs and eventually the whole tree begin to die.

Borers can be prevented or killed by drenching the ground at the base of the tree with a chemical called imidacloprid six weeks before the leaves are fully out. Soon, in other words. It takes that long for the root system to distribute the insecticide throughout the tree.

The treatment lasts for up to one year and can be bought over the counter for small trees. Larger ones require a licensed applicator and cost $6 to $10 for every inch of the trunk’s diameter, says Brandon Hendrickson, president of KC Arborist tree service.

There’s also a spray and an injection many arborists prefer because it’s effective for up to two years and there’s zero risk of runoff.

Again, it can be pricey — $10 to $15 a diameter inch — more than $500 for an older tree that’s three feet across.

But some people think it’s worth it, says Randy Dukes, production manager at Rosehill Gardens.

“I’ve never had anyone balk at the price,” he said.

Not when the cost of removing a dead tree that size could be in the thousands of dollars.

However, none of the treatments are totally effective, advises Kansas State University Research and Extension. Some experts say it might be wiser and more economical to ward off the bugs for as long as possible by good tree care and planting a replacement tree of another species for when your ash does become infested.

“It might not hit their tree for three years, five years, even 10 years,” Lapointe said, but whatever you do: “Don’t just go out and remove an ash tree because it’s an ash.”

That never even occurred to Myer and Rob Levitch, head of grounds maintenance at Timber’s Edge.

For two years they’ve been preparing for their battle with the emerald ash borer. It would cost $500,000, Levitch says, to cut down and replace those 800 ash trees that are the neighborhood signature.

At $10,000 a year for treatment, it would be a half-century of treatments to equal that amount, so treat they will. And who knows, Levitch said, before long “maybe someone at Kansas State or somewhere will find a cure.”

Maybe, says Hendrickson at KC Arborist. But the fact is, it’s not easy beating Mother Nature.

“I’m still cutting down elms with Dutch elm disease,” he said.

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