GREEN MONSTER

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, addressed his team. He was splitting his attention between a map on the wall and his silent team. There were 900 grids on the map. The foresters had done recon on 500. But now, time had run out. “This week is our last real effort,” said Callin. “Then we transition into management.”

Callin and his crew were 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 burrows into ash bark during its three-week lifecycle, laying eggs that gestate over the course of a year. As they grow, the larvae kill the host trees by garroting the trees’ nutrient chain. Within a matter of decades, they are going to kill every single ash tree in New York state. “There is no hope for ash,” mused 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 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 had no choice but to cut their surveillance short and engage the bugs directly because this generation of EAB was about to hatch. With no 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 back as many beetles as they can. “This is going to be what we do for the rest of our careers here,” noted Callin. His two younger foresters—the only members of the group who hadn’t shipped in from elsewhere—nodded their assent.

Callin issued instructions quickly as the crew sipped coffee and shuffled their feet. “We’re going to be peeling in the field today,” he said. “Leave the trees out there.” There is no longer any time to bring the “bolts” of ash back to headquarters for peeling.

The foresters were peeling trees to look for the S-shaped larval chambers that signify EAB infestation. The cambium layer, through which nutrients travel from root to leaf (and where EAB larvae gestate), belies the ashes’ rugged exterior, which is armored with diamond-rutted bark like reptile scales and grows into upward-sweeping bough. Underneath, the meat of the tree is pale and supple. 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.

If a Tree Falls

The DEC assumes that EAB came to the Catskills in firewood. Until the summer of 2010, the EAB’s only presence in New York was in the far western region. Similarly, the U.S. Department of Agriculture 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 their 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, assistant professor of forest entomology at SUNY College of Environmental Science and Forestry, 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 spends his days driving from town to town, tying purple ribbons onto ashes so that people can figure out just what, exactly, an ash is. The problem with invaders is that nobody ever knows the risks ahead of time. “Twenty years ago,” said 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 predators to combat EAB—although Congress has recently cut the USDA’s budget.

The Forest Service has forked over $200,000 to the 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 Partnership 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 didn’t turn up any sign of EAB. The veterans used 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 warned the volunteer as they all set to work peeling bark off of ash bolts with draw knives. He was 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, explained tree-felling to the volunteer: “It’s a lot like hunting,” he said. “Once you pull the trigger, the fun’s over.”

At the next site, which was flatter but denser, Callin and Paul assaulted alternating trees with two chainsaws. After the first tree, a younger, thinner ash, was down, Callin grabbed a draw knife and dug into a bolt. Within seconds, he found what he was looking for. “Look at this,” he said, pointing to a jagged zig-zag in the flesh of the bolt. “EAB.”

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

Bored to death: Dr. Melissa Fierke, assistant professor of forest entomology at SUNY College of Environmental Science and Forestry, has been researching the efficacy of staving off the Emerald Ash Borer infestation with digger wasps. Part of the strategy of studying these pests are purple prism traps (above, right), devised by the U.S. Department of Agriculture to trap the EAB for researchers. This one hangs from a tree at Onondaga Lake Park, though you can spy them throughout upstate New York, southern Ontario and northern Pennsylvania. Evidence of EAB infestation (center) displays the parallel tunneling pattern found just beneath the barked surface of the ash tree.

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

The gallery, much cleaner than the one Callin himself had found, showed telltale EAB damage. Callin began digging at the chamber with his pocketknife and finally inched 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,” said Callin. Then, agitated by remembering something the landowner had said, “on a property that supposedly had no ash.” Callin grew more cheerful, stoked that the DEC’s projections of the infestation were 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,” continued 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.

The Worm Turns

Fierke, along with a team of research assistants, has been experimenting with solitary digger wasps. They have covered certain nests with black sand, hoping to trap heat from sunlight in order to dupe the wasps incubating underneath into thinking that summer has come early and hatching before they ordinarily would. 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,” explained Fierke, “the larvae eat the paralyzed beetles. It’s kind of macabre.”

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.

Meanwhile, in an effort at “biocontrol,” or trying to use one species to decrease numbers of EAB, 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,” said 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.”

However, 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 native of Washington state, 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 coordinate 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 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 then affixed some plastic cards to the ribbon, explaining the threat of EAB to ash trees. “I know it’s goofy,” he joked, “like, jeez, another ribbon around the tree.”

As the purple ribbon movement has picked up steam, Whitmore has found more volunteers, 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 crowed.

“One of the numerous utility companies in New York alone manages about 66,000 miles of transmission line right-of-way,” he added. If an ash drops on a power line and power goes out, the company that owns the line is on the hook for repair. “They’ve been hiring a lot of people to clear trees around the lines.”

Whitmore has helped form a task force in Ithaca 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. 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 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, so it is expensive to control EAB and then there is no place to put the chips. “We’ve got nowhere to put them when we chip up infested trees,” explained 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.”

Michael Epstein smoked a thin cigar and clambered up and down a ladder, cleaning his gutters as Callin’s crew scrambled around the woods behind Epstein’s yard near Kingston. In a cutoff T-shirt that showed off his shoulder tattoo, he kept a loose eye on his young son, who was playing in the backyard playground.

Paul was hard at work with his chainsaw.

The ashes he was dropping at this site were huge in comparison to the younger trees he had felled earlier in the day, and they arced downward in slow motion with wet, echoing snaps and cracks before the final, thundering percussion.

The peeling had grown epic in proportion to the chopping. The crew couldn’t stand the bolts upright on account of the logs’ girth and weight. They peeled with the bolts lying lengthwise on the ground, rolling them as they peeled to expose unpeeled bark and diving relentlessly back in. The bolts were now taking upward 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.

The crew finally found larvae in one of the massive logs. Callin grooved on the find, elated for about a second before he quickly deflated, his victory spoiled by the realization that he had to give Epstein the bad news. After ditching his chaps and hardhat, Callin trudged up the sloping property to confront Epstein. He explained that the presence of the beetle meant that all of Epstein’s ashes—including a six-story colossus poised menacingly over his son’s playground—were slated for death, and in short order.

“It’s terrible,” said Epstein, a little shellshocked. “Just terrible.”

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

“Somebody’s gotta write a grant,” protested Epstein. Then, more vehemently, “I’ll write a grant. What can we do?” At a loss, Callin left the question unanswered. The crew assembled their gear and packed up the trucks, eager to get home to families and dinner. It had 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 said encouragingly to Callin before they parted ways. It would be another long day.

Beat the beetles: Melissa Fierke holds a T-shirt that shows the only known enemy of the Emerald Ash Borer, digger wasps, given the moniker, “The Beetle Bandits.” Later on, she shows off an EAB specimen affixed to paper to display how small the insect really is.