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Logging to fight spruce bark beetles and remove dead trees has sparked protests.


Beetles are ravaging Europe’s oldest forest. Is logging the answer?

BIAŁOWIEŻA, POLAND—It’s a cool, gray day in early October, and the town of Białowieża in northeast Poland looks peaceful. But outside a three-star hotel, some two dozen environmental activists have gathered, wearing masks with a photo of Poland’s minister of the environment, Jan Szyszko, and white T-shirts that say “I’m a liar.” There’s a rumor that Szyszko is coming to town today. Just opposite the activists, a similar number of people hold banners supporting him, some wearing hard hats and safety vests and others in camouflage hunting outfits. Police cars are pulling up; an ambulance is parked nearby just in case.

Białowieża (pronounced be-ah-wo-VE-zha) is the gateway to Europe’s most primeval forest, famous for its giant oaks, wild bison, wolves, and woodpeckers. The town is also the center of a battle about the future of the forest—a conflict that has sharply divided Poland and pitted foresters against ecologists and other researchers. The issue has even widened a rift between the country’s conservative “law and justice” government and the European Union.

State Forests, the government organization that manages most Polish forests, claims that Białowieża Forest is in jeopardy from an outbreak of the spruce bark beetle (Ips typographus), a voracious insect that kills weak spruce trees. It says logging is the only way to stop the threat. Last year, Szyszko tripled the amount of logging permitted in part of the forest. Environmental groups and many ecologists say the ministry’s cure is far worse than the disease, and that nothing less than the future of Europe’s last ancient wilderness is at stake.

Today, the protesters’ audience is a group of foreign delegates, arriving from an international forestry conference in Warsaw for a tour of the forest. (Szyszko doesn’t show up, but a deputy arrives behind the hotel in a black sedan.) As loudspeakers blare slogans, two protesters without masks or signs have slipped past the burly forest guards into the hotel lobby in an attempt to reach the international experts. A young woman whose right hand is bandaged—an injury from a previous protest, she says—quietly urges the visitors to come see for themselves the damage from the flurry of logging.

Both sides in this battle say they want to protect Białowieża Forest. And both claim to have science on their side. State Forests, backed by its own scientists and academic forestry researchers, is even embarking on a major new study, itself controversial, to show that selective logging will sustain biodiversity, not harm it.

But in the end, more research won’t resolve the conflict over Białowieża, says Jaboury Ghazoul, a forest ecologist at ETH Zurich in Switzerland. “What kinds of forests do we want to end up with? That’s largely a question of values,” he says. “It’s not something that can be easily resolved, if at all, by science.”

Spruce add to the diversity of Białowieża Forest.


The crown jewel of Białowieża is the 48-square-kilometer “strict reserve” within the national park, which visitors must enter with a guide. Past a massive wooden gateway, the canopy is dominated by majestic oaks that tower 40 meters overhead. Here and there, the tallest spruce trees extend 8 meters higher. Below the canopy, hornbeam and linden trees are turning golden. Even more species wait as saplings for a giant to die and let in enough light for them to grow.

The park is an important wildlife haven as well. Wolves and lynx roam in and out. Heavy-shouldered bison make up part of the largest remaining population in Europe. The forest has a rich array of birds, especially woodpeckers and owls, as well as almost 10,000 insect species and 1850 kinds of macrofungi, most of which thrive on the abundant dead wood that litters the forest floor. Many are found only in Białowieża Forest and are listed as endangered. “We have a treasure,” says Rafał Kowalczyk, who directs the Polish Academy of Sciences’s (PAN’s) Mammal Research Institute here. And it’s not limited to the park.

The larger Białowieża Forest, which extends beyond the national park and covers about 1500 square kilometers, has been protected for more than 600 years. King Władysław II Jagiełło, a Polish national hero, is said to have hunted here before he defeated Teutonic knights in 1410. Soon after, the forest was declared a royal hunting ground. It wasn’t until World War I that industrial-scale logging began. In later decades, foresters replanted clear-cuts as plantations of spruce and pine.

Polish scientists worked to protect the least spoiled area of forest with the greatest density of big trees, first as a nature reserve and then as a national park in 1932. The park was eventually expanded to 105 square kilometers, 17% of the Polish portion of Białowieża Forest. Across the border, Belarus has a similar mix of strictly protected and managed areas. Most of the forest is a UNESCO World Heritage Site.

State Forests takes great pride in managing its share of Białowieża Forest. It’s proud of its history, too. During World War II, staff hid anti-German partisans in remote parts of the forest. After the war ended, the Communist Party gave peasants a chance to advance through forestry. Today, State Forests employs nearly 25,000 people and manages 84% of Poland’s vast tracts of forest.

Past logging has razed more than a third of Białowieża Forest, but much old-growth—defined as a stand of trees in which at least 10% are older than 100 years—survives on land managed by State Forests. Some was put off-limits as nature reserves in 2004. The remainder was temporarily protected by Poland’s previous, liberal government in 2012 through a 10-year management plan that also slashed timber quota by 60%. These protective measures were hard-won compromises between opponents of logging and State Forests and its supporters.

Some scientists argue for expanding the national park, which would make more tracts of forest off-limits to logging. "There's enough public support in the nation for protection of the forest," says Eunice Blavascunas, a cultural anthropologist at Whitman College in Walla Walla, Washington, who has studied the controversy for yearsPolish politicians might agree if they saw the value of nature tourism, says Wiesław Walankiewicz, an ornithologist at Siedlce University of Natural Sciences and Humanities in Poland, who estimates that value at $20 million to $25 million per year. More than twice as many locals now work in tourism than for State Forests, he notes. Sławomir Droń, a cafe owner here, agrees. “Our money is not in cutting trees,” Droń says as he pours a craft beer named after the bark beetle and brewed with spruce needles from Białowieża.

But the government has actually increased logging in parts of Białowieża by revising the 2012 plan. The national park and nature reserves—which together make up about 36% of the Polish side of the forest—are not in play. The battle is over a comparably ancient and cherished habitat: old-growth stands in the managed forest, particularly those rich in spruce.


The ravages of the spruce bark beetle are visible just a few kilometers outside town, on a narrow dirt road lined with dead spruce. Gray branches rustle in the wind. Just this spring they were green, says Dariusz Skirko, superintendent of Białowieża Forest District, where most of the new logging has taken place. “This dieback of trees is progressing very fast,” he says.

The half-centimeter-long spruce bark beetles can kill a mature tree within months, especially one weakened by drought. Since 2012, a dry spell has sustained the current outbreak. “If we go across the forest, you can see dead trees all over the place,” Skirko says.

Jacek Hilszczański, an entomologist with State Forests and the Forest Research Institute in Sękocin Stary, says an extra-ordinary number of bark beetles were flying around sampling traps earlier this year. “I was amazed,” he says. “I haven’t seen such an intensive swarming before.” Removing infested trees before the beetle offspring mature is the only way to curb the threat, foresters argue. This approach worked during past outbreaks, Hilszczański points out, before logging was more widely restricted. Now, more than 7500 hectares of spruce stands are dead, perhaps one-third of all spruce trees in the forest, Hilszczański estimates.

Other experts say the strategy can only control the small outbreaks that occur when small patches of trees are stressed. “The big outbreaks don’t work that way,” says entomologist Diana Six of the University of Montana in Missoula. “You can’t stop them.” Nor should you, ecologists add: Bark beetle outbreaks should be allowed to happen as part of the forest’s life cycle, and the dead spruces provide habitat for many species.

On a tour of several logging sites, Adam Bohdan, a biologist with the Wild Poland Foundation in Warsaw, is eager to demonstrate the damage logging has caused. On both sides of a dirt road near town, spruce logs are stacked more than 3 meters high. Activists have stenciled the largest ones with spray paint: “This tree is more than 100 years old.” The soil is deeply rutted from the giant harvesters, which can topple a tall tree and strip its branches in minutes.

Bohdan swings a hand ax at a felled tree. Ripping off a piece of bark, he points to a wiggling beetle larva. It’s Cucujus cinnaberinus, an endangered species that feeds on dead trees, and one example, Bohdan says, of why it’s harmful to remove the dead trees. At a nearby site, the dead spruces have been clear-cut and trucked away. Pines and birches have suffered collateral damage from the cutting.

State Forests says it isn’t just fighting the bark beetle. It is also waging a longer term campaign to protect the forest from a change in tree composition. Since the 1930s, the amount of young oak has declined, whereas hornbeam in particular has become more common, according to an analysis of the strict reserve led by Bogdan Brzeziecki, a forestry scientist at the Warsaw University of Life Sciences. Hornbeam resists grazing and browsing much better than other species, an advantage as red deer have become more abundant.

Another key factor is that young oak require plenty of light to mature. Today’s big oaks grew up in forest patches that were relatively open; over the past century, these parts of the forest became shadier as villagers abandoned small-scale clearings, which have since become overgrown with hornbeam and other species. This has also caused a decline in associated plants, insects, and other species. So foresters have been creating new fields of oak, primarily by removing stands of dead spruce and planting oak seedlings, then cutting any hornbeam that tries to muscle in. Fences keep out bison and other herbivores, which may trample or eat seedlings. Brzeziecki says more clear-cutting would increase the odds of success. “If we do nothing, we might have no oak at all,” he says.

Dead wood in Białowieża hosts many fungi, such as the clustered bonnet (Mycena inclinata).


Ecologists don’t see the need to fight the increase of hornbeam. “For a forest, change is natural, not stability,” says forest ecologist Bogdan Jaroszewicz, who directs the University of Warsaw’s Geobotanical Station here. The forest is large enough that no tree species will disappear. And restoration shouldn’t happen in stands that had a natural origin, because they have centuries-old trees and many dependent species.

There’s less harm in removing monoculture spruce plantations and replanting with oak and other broadleaf species, ecologists say. But they maintain that dead spruce should be left in place even in beetle-stricken plantations. A hands-off approach would lead to a community with trees of various ages, which can benefit other species; fences wouldn’t be needed, so bison could wander in and feed on grass. Research in the park also suggests that young oak and other seedlings will be protected from deer when they sprout in a tangle of dead spruce.

But most foresters hate to “waste” dead spruce trees by leaving them in the forest, and they are skeptical that natural regeneration will occur widely, particularly for oak. “We can only hope it will happen,” Brzeziecki says. “I don’t want to wait.”

Experience elsewhere offers little guidance. The concept of using logging to benefit forest biodiversity has been gaining currency in the U.S. Pacific Northwest. However, this is intended to diversify habitat types mostly within dense conifer plantations. Most scientists don’t think the same strategy is appropriate within the old-growth forest of Białowieża.

The conflict has reached Europe’s highest court. After the environment ministry tripled the logging quota in March 2016, eight nongovernmental organizations (NGOs) accused it of breaking EU nature protection laws by not assessing the potential ecological impact of the additional logging and not sparing trees more than a century old. The NGOs appealed to the European Commission, which took the case to the European Court this past July and asked for expedited proceedings because of the risk of “irreparable harm” to the ecosystem. Within a month, the court ordered a temporary halt to the logging while it evaluates the case.

Because the ban has an exemption for public safety, State Forests switched to cutting dead and dying trees near roads and trails, where it says they could fall and cause accidents. Last month, the court clamped down on that, too, saying that logging for public safety could only happen when strictly necessary. The ministry maintained in a statement that it had never violated EU regulations, and the logging continues, although more slowly and with chainsaws rather than harvesters. The hearing on the quota is scheduled for 12 December, and Agata Szafraniuk, a lawyer at the environmental nonprofit ClientEarth in Warsaw, expects a ruling next year.