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If a Tree Falls, Will They All Fall?

Conservationists scramble to act as invasive boring insect spells certain death to much—if not all—of New York state’s ash tree population

by Alex Gecan on July 6, 2011

In one corner of a long, barely lit room, standing in a spot that had been swept clean of the peeled ash bark that littered the rest of the space, Mike Callin, head forester for the Department of Environmental Conservation in Lake Katrine, addresses his team. It is already mid-May, but it is still chilly in the Catskills. Callin is dressed in a brown pullover jacket and tattered khaki trousers. He splits his attention between a map on the wall and his silent team. There are 900 grids on the map. The foresters have done recon on 500. But now, time has run out. “This week is our last real effort,” says Callin. “Then we transition into management.”

Callin and his crew are saddled with the impossible task of tracking an infestation of an invasive insect—the emerald ash borer, or EAB—across more than 200 square miles of forest, towns and private land. EAB is a tiny wood-boring beetle that feeds only on ash trees during its one-year life cycle. Eggs laid in the summer hatch and burrow into the inner bark of the tree. As they grow, the larvae kill the host trees by garroting the trees’ nutrient chain. Within a matter of decades, they are likely to kill every single ash tree in New York state. “There is no hope for ash,” muses Callin.

Ashes make up 7 percent of New York’s forests and, outside the largely coniferous Adirondack region, they account for a much larger denomination (including 11 percent of the state’s hardwood). They are integral to recolonization of deserted fields, and hold together the state’s wetlands. They are also popular street trees, since they have a root structure that copes well with adverse conditions—which means that many towns and cities will have to deal with dying, falling trees.

The foresters have no choice but to cut their surveillance short and engage the bugs directly, because this generation of EAB is about to hatch. With no effective natural predators on this continent, EAB’s success rate at killing ash trees is 100 percent. But Callin and his crew are dead-set on holding as many beetles back as they can. “This is going to be what we do for the rest of our careers here,” says Callin. His two younger foresters—the only members of the group who haven’t shipped in from elsewhere—nod their assent.

Callin issues instructions quickly as the crew sips coffee and shuffles their feet. “We’re going to be peeling in the field today,” he says. “Leave the trees out there.” There is no longer any time to bring the “bolts” of ash back to headquarters for peeling. The new strategy is to “leapfrog” from grid to half-mile grid, two teams checking in with each other as they go.

The foresters are peeling trees to look for the S-shaped larval chambers that signify EAB infestation. They grind off the trees’ bark to get a look at the cambium layer, the layer through which water and nutrients flow from root to leaf. The cambium layer belies the ashes’ rugged exterior, which is armored with diamond-rutted bark like reptile scales and grows into upward-sweeping boughs with opposing branches. Underneath, the meat of the tree is bright and supple, like clammy, sweaty flesh. When the trees are infested, great brown scabs of dead wood radiate out from the crusty, meandering larval galleries.

So far, the ash borer has killed 25 million trees in North America since it first arrived in Michigan in the early 1990s, a hitchhiker in wooden shipping material. It has also caused millions of dollars in damage and, according to the Western New York Partnership for Invasive Species Management, it will cost the United States another $10 billion over the next decade.

The DEC assumes that EAB came to the Catskills in firewood. Until the summer of 2010, EAB’s only presence in New York was in the far western region. Similarly, the USDA assumes that EAB came to America in wooden shipping materials, but since the infestation (which began in Michigan in 1992) wasn’t discovered for a decade, there is no way to be sure.

It was a USDA tool that first detected the marauding insect in Ulster County last July. One of the department’s “Purple Prism Traps”—stylized flypaper designed to trap EAB—caught a single beetle in the woods outside Saugerties, which Callin and the rest now call “ground zero” for the infestation. Like a single plague rat, it means the eventual death of all of the ashes in the Catskills.

The infestation has fueled innovation across the state. Dr. Melissa Fierke, a professor at SUNY College of Environmental Science and Forestry in Syracuse, has figured out a way to turn insect on insect. She has been fiddling with solitary digger wasps, which eat EAB, to turn them into even better beetle hunters than they were to begin with. Mark Whitmore of Cornell University has begun a “purple ribbon project” so that New Yorkers can identify ashes. Meredith Taylor runs urban tree surveys—the city-slicker companion to Callin’s forest surveys—out of the Catskill Center for Conservation and Development.

This particular beetle just happens to be the most current, pressing threat to New York state’s ecosystems. From EAB in the north and west to the Asian longhorn beetle in the south, insects are only one component of a cornucopia of death, a series of invaders from all walks of life that are threatening New York’s biodiversity. Japanese yarberry, a stalklike opportunist, and Japanese knotweed, a leafier vine, grow into deforested land. Foreign water chestnut and Chinese mitten crab gobble the Hudson River’s dissolved oxygen and microbial food. Northern snakehead, a toothy, goblinlike fish with an insatiable appetite and the ability to survive for days on dry land, have begun starving out native fish in Queens. The problem with invaders is that nobody ever knows the risks ahead of time. “Twenty years ago,” says Whitmore, “I never would have thought of a member of the genus Agrilus (EAB’s subgroup) as a tree killer.”

Whitmore, Fierke and the rest have some help from the state and the feds. Sen. Chuck Schumer has lobbied the USDA on the state’s behalf, and they are working on parasitic predator wasps to combat EAB—although Congress has recently cut the USDA’s budget. The USDA Forest Service has forked over $200,000 to the state DEC to deal with the infestation, and the state Department of Agriculture and Markets is also cooperating with counties and cities to fight off the aliens. Agents from these organizations work with county officials and local conservationists in “Partnerships for Regional Invasive Species Management” (PRISMs). But in a cash-strapped state at the butt end of a recession, procuring funding is always a tricky question—and the beetles aren’t waiting on the bureaucracy’s convenience to hatch.

The first survey grids on Callin’s hit list don’t turn up any sign of EAB. The veterans use it as an opportunity to give their one inexperienced volunteer an impromptu training session in basic forestry. “Make sure you don’t cut your nuts off,” a forester warns the volunteer as they all set to work peeling bark off of ash bolts with draw knives. He is only half-joking: A few weeks earlier, a DEC employee had pulled one of the twin-handled, razor-sharp scythes down a bolt of ash and straight into his knee.

Matt Paul, a 32-year-old forester, explains tree-felling to the volunteer: “It’s a lot like hunting,” he says. “Once you pull the trigger, the fun’s over.”

At the next site, which is flatter but denser, Callin and Paul assault alternating trees with two chainsaws. After the first tree, a younger, thinner ash, is down, Callin grabs a draw knife and digs into a bolt. Within seconds, he finds what he is looking for. “Look at this,” he says, pointing to a jagged zigzag in the flesh of the bolt: “EAB.”

There is a murmur of dissent. There is the signature crusty gallery, wending its way back and forth, and a layer of dead wood around it; but the shape of the tunnel is too irregular. EAB travel in parallel tunnels, left to right, then a brief descent, then right to left, and repeating. This gallery is too haphazard. “That’s native,” mutters Hasbrook, the youngest and newest member of the crew. The chamber holds a beetle larva, but it is a different species, one that doesn’t pose a threat anymore, one with natural predators in the area.

Hasbrook and two other foresters set to work on Callin’s second tree. The two older woodsmen don’t find anything, but suddenly, Hasbrook calls out, “Mike! I got it!” He holds the offending bolt over his head like a trophy.

The gallery, much cleaner than the one Callin had found, is telltale EAB damage. Callin begins digging at the chamber with his pocketknife and finally inches out the milky white larva hiding inside, its body like a squirmy drywall screw, notched and cylindrical with a bulbous head, barely similar to its pearlescent green parents except in size.

“We got it,” says Callin. Then, agitated, remembering something the landowner had said, “On a property that supposedly had no ash.”

Callin grows more cheerful, stoked that the DEC’s projections of the infestation are roughly accurate. “Finding an early larva here as you get in closer to ground zero, it means that we’re getting closer.”

“We’ll put in trap trees somewhere in this area,” says Callin. That means they will begin to peel live trees, a death sentence for the ashes they peel but a beacon of hope for the ones they don’t. This will be the “management” phase of dealing with the infestation.

The peeling process—called “girdling” when applied to live trees—stresses the ashes into releasing pheromones that attract adult beetles, tricking the mature population into depositing their eggs in a few select trees. Even though the ashes that the foresters choose to girdle will die within a few years, their martyrdom helps to isolate many of the next generation of EAB larvae rather than letting them spread to the rest of the ashes in the forest.

With silent effort, Dr. Melissa Fierke balances a 4-foot piece of rebar against her hip, squatting slightly to keep it pointing straight up. With a brief glance around to make sure it’s in the correct position, at one point of a long rectangle demarcated with three other lengths of rebar, she begins hammering it into the sandy earth with the handle of a wood awl.

Under the rectangle of hard-packed earth are nests of incubating solitary digger wasps. On the surface within the rectangle, Fierke and her assistants have set up six square landscaping barriers, three of which are filled with a thin layer of black sand. They want to dupe the wasps into hatching early, hoping that the black sand will trap heat from the sun and trick the wasps into thinking it is time to come out and hunt. If the ruse works, the wasps will hatch at the same time as the generation of EAB incubating to the east and west of Fierke’s outpost, which is just north of Syracuse. Fierke is trying to turn the wasps into an even more effective tracker of EAB than it already is.

Dr. Steve Marshall of Ontario’s University of Guelph—or rather, Marshall’s son—discovered the wasps’ affinity for EAB. Marshall, who had been researching EAB (which are also devouring ashes in southeastern Canada), had taken his son camping. The 12-year-old spotted a wasp lugging a pearly green beetle and called out, “Dad, this wasp is eating that beetle you like!”

The digger wasp hunts ash borers and other similar beetles, paralyzing them and dragging them back to the wasps’ nest for larvae to eat as they develop. “Once there are enough beetles and the eggs hatch,” explains Fierke, “the larvae eat the paralyzed beetles. It’s kind of macabre.”

One of Fierke’s assistants lifts her head from where she was pounding in a landscaping barrier and corrects Fierke. “It’s kind of awesome.”

Fierke and her team call what they’re doing with the digger wasp “biosurveillance,” or using one organism to track another. In New York, this is as far as anyone has gone to use predators or parasites to slow down or even track the ash borer.

USDA scientists at Michigan State University have identified two insects that lay eggs in EAB larvae and one mold that also eats the immature beetles, killing them off at a rate of up to 90 percent in a laboratory setting. But this is “the first biocontrol project ever against [this type of] beetle,” says Dr. Juli Gould, who works for USDA’s Animal Plant and Health Inspection Service (APHIS). “It is too early to tell if this program will work.”

And the USDA cannot yet release the parasitoids into the wild. The parasites, which are non-native just like the ash borer, might go invasive the same way the beetles have—they simply don’t know yet whether the predators will start killing off species other than EAB.

Mark Whitmore, a 55-year-old Washington state native, is a forest entomologist and head of Cornell University’s department of natural resources. He works out of his car as well as Cornell, traveling across the state to set up local partnerships to manage invasive species. Besides conducting his EAB research project, he frequently travels throughout the state coordinating the Cornell Cooperative Extension EAB outreach program.

Last summer, Whitmore decided that people should at least be able to identify ash trees so they could begin making plans before the trees started dropping on their own. He went to a gift store and bought up spools of purple ribbon. He ordered some purple surveying ribbon from a forestry supply company. Then he and a number of volunteers from the city started walking around Ithaca’s public parks, tying off lengths of ribbon around each ash. He dedicated some of his funding to building information kiosks, and affixed plastic cards to the ribbons explaining the threat of EAB to the ash trees. “I know it’s goofy,” he jokes, “like, jeez, another ribbon around the tree.”

As the purple-ribbon movement has picked up steam, Whitmore has found more volunteers around the state, and they have begun adding information cards to the purple garters; they have covered a great deal of Ithaca and intend to keep going. “Now people can say, ‘Oh, that’s an ash tree,’” Whitmore says.

Whitmore leads students down toward the gorge at the rear of Cornell’s campus, chatting as he goes. “One of the numerous utilities companies in New York alone manages about 66,000 miles of transmission line right-of-way,” he says. If an ash drops on a power line and power goes out, the company that owns the line is on the hook for repair and also for hefty fines. “They’ve been hiring a lot of people to clear trees around the lines,” he says.

Whitmore has helped form a task force in Ithaca, as well as in other locations in the state and elsewhere, to keep an eye out for EAB. “There were people at Cornell, Ithaca College, and in the city of Ithaca who were all thinking about what to do,” he says. “We realized we would be better off working together and bringing in other partners in the county.” So he started holding meetings in his department building. The group grew. Now, Whitmore is gearing up to deal with yet another major EAB project: getting rid of wood chips.

It’s too risky to transport infested timber during the beetles’ flight season, so burning it or chipping it down are the only options. But there is only a very small market for chipped ash, and then there is no place to put the chips. “We’ve got nowhere to put them when we chip up infested trees,” says Whitmore. “If there was a market for the chips, like turning them into wood pellets, the cost of control would go down and there would be a place for the chips to go rather than in a landfill.”

Whitmore takes the long view, asserting that every dollar spent on containment, quarantine and education will save several dollars in the future. “People don’t pay attention until it’s in their backyard,” he says. And since state agencies are on the hook only for trees in state forests, and the utilities companies only have to watch out for their own power lines, landowners have to foot the bill if they decide to remove any of their own trees—and it can costs hundreds if not thousands of dollars to cut down and remove a larger tree near a home.

Whitmore also is stuck in a constant game of catch-up. “One of the real hard things about this bug,” he says, “is that we’re relying on traps that are pretty inefficient,” referring to the purple prism traps that caught a single beetle out of the entire Saugerties infestation.

Despite all this, Whitmore is not fazed by EAB’s kill rate. He knows that “it’s not a question of if, but when” the entire ash population will die out, but he banks pretty heavily on how long he can stretch that “when.” “Ninety-nine-point-two percent of the state is not infested,” he says. “Now is not the time to throw up our arms. No, now is the time to act and slow the spread so we can buy time to plan ahead.”

Meredith Taylor stares into the camera, barely blinking, forcing a rigid posture on an antique wooden stool. She fidgets with her sweater, shifting in her seat. It is her first on-camera appearance. Her blue eyes wide, her normally soft voice shaking just slightly, she begins her on-screen debut. “Hi, I’m Meredith Taylor, coordinator of the Catskills Regional Invasive Species Partnership, and I’m here to talk to you about an invasive insect—”

The rest of her sentence is drowned out by a loud crash and a series of bells tinkling. An elderly couple, walking down Main Street in Saugerties, had not noticed the makeshift, handwritten “closed” sign on the door of Fox and Crane, the antique shop where Taylor is starring in her first commercial, surrounded by peeling furniture, dusty action figures and Coca-Cola posters.

“It’s all right, we can cut around that interruption,” says the cameraman.

“That interruption,” hisses the shop owner, “was a customer.” The cameraman clams up. The shop owner is sacrificing business to make this commercial happen.

Taylor, a 25-year-old conservationist, is responsible for drumming up enough volunteers in Saugerties to run an urban survey, the kind the DEC doesn’t have time or manpower enough to accomplish. Ordinarily, she works out of the Catskill Center for Conservation and Development, a workshop-cum-museum nestled in the idyllic hills of Arkville, a tiny hamlet on Highway 28, about 30 miles off the Thruway.

The workshops she has run out of the Catskill Center have had good turnout, but poor results. “There were people falling asleep in their seats,” she recalls. After all, she was making a hard sell—she had to convince people to find ash trees, and then stand at the bases of them, staring through binoculars at every square inch of bark, scoping for signs of infestation.

Local organizations like the Catskill Center rely on independent funding, and that only gets them to the point of running public-access commercials starring their own employees. The response to the commercial was slightly better than the response to the workshops, but the community’s response still didn’t meet its needs. In the end, the man who shot the ad and the woman who owned the store also had to walk the last two routes of the survey. Only 11 other local volunteers walked the streets to see which trees might soon topple.

Michael Epstein smokes a thin cigar and clambers up and down a ladder, cleaning his gutters as Callin’s crew scrambles around the woods behind Epstein’s yard. In a cut-off T-shirt that shows off his shoulder tattoo, he keeps a loose eye on his young son, who is playing in the backyard playground.

Callin’s crew has grown by two since lunchtime. A pair of young foresters from Lowville has joined their ranks, injecting a fresh surge of the levity that had subsided since the group first met in the bark-strewn headquarters in Lake Katrine. “That’s a nice piece of white ash you got hanging on your pecker,” one ribs the other, as they set to work on their first bolts of the day.

Paul is hard at work with his chainsaw. He has discarded his green fleece vest, but in his neon orange Kevlar chaps, hardhat and mesh visor, wielding his chainsaw with elegant precision, he strikes an image like a child’s vision of a sci-fi villain, hooded and helmeted, his chaps like a blacksmith’s apron. The ashes he is dropping at this site are huge in comparison to the younger trees he had felled earlier in the day, and they arc downward in slow motion with wet, echoing snaps and cracks before the final, thundering percussion.

The peeling has grown epic in proportion to the chopping. The crew can’t stand the bolts upright on account of the logs’ girth and weight. They peel with the bolts lying lengthwise on the ground, rolling them as they peel to expose unpeeled bark and diving relentlessly back in. The bolts are now taking upwards of 10 minutes each to peel, while the younger, smaller bolts had required only a fraction of that time when the day was younger and the crew better rested.

They finally find larvae in one of the massive logs. Callin grooves on the find, elated for about a second before he quickly deflates, his victory spoiled by the realization that he has to give Epstein the bad news. After ditching his chaps and hardhat, Callin trudges up the sloping property to confront Epstein. He explains that the presence of the beetle means that all of Epstein’s ashes—including a six-story colossus poised menacingly over his son’s playground—are slated for death, and in short order.

“It’s terrible,” says Epstein, a little shell-shocked. “Just terrible.”

Callin explains that there is only so much DEC can do to help out with infestations on private land. Ultimately, Epstein is going to have to absorb the cost of felling the trees. “It’s a question of funding,” Callin explains.

“Somebody’s gotta write a grant,” protests Epstein. Then, more vehemently, “I’ll write a grant. What can we do?”

At a loss, Callin leaves the question unanswered. The crew assembles their gear and packs up the trucks, eager to get home to families and dinner. It has been more than 10 hours since they had stood around sipping coffee and planning the day’s strategy.

“I’ll be in early tomorrow,” Paul says encouragingly to Callin before they part ways.

It would be another long day.

Alex Gecan is a freelance writer and a researcher and Web editor for New Orleans Magazine and myneworleans.com He lives in New Orleans.