The Tree That Ate the West

Both native and invasive—protected and reviled—western junipers are a living contradiction.

At the Flatiron Rock Trailhead in central Oregon’s Badlands Wilderness, a gnarled stump reaches out of a crack in the rocks. A centuries-old juniper tree stood here until last December, when vandals illegally cut it down and hauled it away.

“That tree is probably a lamp somewhere now,” says Gena Goodman-Campbell, wilderness coordinator for the Oregon Natural Desert Association, as she looks at what’s left. A $1000 reward offered by ONDA and other local environmental groups has failed to turn up any leads.

Old-growth western junipers (Juniperus occidentalis) are stooped and twisted, their furrowed red bark typically blanketed in lichen. No two are alike, and Goodman-Campbell points out one favorite after another as she works her way up the trail. This one’s roots have split a massive boulder; that one’s limbs are so bent they rest on the ground. Although junipers typically grow no taller than thirty feet, an individual might live for more than a thousand years—a tree a few miles south of here was dated at 1,600 years, and there are likely others even more ancient. These trees are irreplaceable, and cutting one down on public land is punishable by a fine of $100,000 and up to a year behind bars.

Strange, then, that while the Bureau of Land Management (BLM) is hunting for the Badlands timber poacher, it’s also ramping up efforts to remove western juniper from large swaths of eastern and central Oregon—in an attempt to restore the region’s sagebrush steppe ecosystem. Over the past 130 years, changes in land use and management practices have allowed juniper woodlands to expand their geographic range tenfold, profoundly altering the ecosystems they infiltrate. Today, land managers in Oregon and several other western states are struggling to regain some control over invading junipers even as they strive to protect the remaining old-growth stands not far away. Both native and invasive, the western juniper is a living contradiction. And like many stories of transformation in the American West, this one starts with the arrival of white settlers and their cattle.

Like many stories of transformation in the American West, this one starts with the arrival of white settlers and their cattle.

Conifers tend to be sensitive to fire, and historically, junipers survived the fires that regularly swept across the arid inland west by carving out niches safe from the flames. They took root in inhospitable patches of habitat where the grasses that fueled the fires couldn’t grow—rocky surfaces and steep slopes with shallow soils and little moisture.

But beginning around 1870, settlers turned large numbers of cattle loose to eat the native grasses that grew among the sagebrush. This left less fuel for fire, and between this and a widespread campaign to suppress fires across the American West, soon nothing was keeping junipers confined to their steep, rocky sanctuaries. Now, when a robin perched on one of those gnarled branches to gulp a juniper berry, chances were good that the seeds would grow undisturbed wherever the bird happened to drop them. Across the region, juniper populations exploded.

Given the opportunity, juniper trees outcompete the grasses and shrubs of the sagebrush steppe. In extreme cases, nothing but bare soil and shallow-rooted invasive grasses remain between the trees, dramatically decreasing habitat quality for many species. Sagebrush-dependent songbirds like the Brewer’s sparrow (Spizella breweri) and the green-tailed towhee (Pipilo chlorurus) have nowhere to nest. Bighorn sheep (Ovis canadensis) and pronghorn antelope (Antilocapra americana) become more vulnerable to mountain lions (Puma concolor), which use junipers as cover to stalk large prey.

The spread of juniper can also reduce water availability in an already-parched landscape. Despite their drought tolerance, a single mature juniper can consume 10 to 30 gallons a day, pulling water from nearby streams and springs. While this affects native wildlife, it’s had an even greater impact on the cattle ranchers who for generations have come to depend on the sagebrush ecosystem’s natural resources. As water and native grasses become scarce, the number of cattle a piece of land can support plummets. Depending on the site and how advanced the juniper growth is, the tree’s invasion can decrease the amount of forage by 30 to 90 percent. The Oregon Cattlemen’s Association has called juniper “one of our most noxious invasive species.”

Still, no animal is more emblematic of the sagebrush steppe in trouble than the greater sage-grouse (Centrocercus urophasianus). These iconic western birds about the size of barnyard hens gather each spring in groups called “leks.” Here, the males inflate yellow air sacs in their chests, spread their fanlike tails, and dance for the approval and attention of the females—a display so show-stopping that many people have dubbed them America’s birds of paradise. Unfortunately, these reproductive spectacles have become increasingly rare as the species’ population has plummeted 80 percent since 1960, primarily due to habitat loss.

The sage-grouse is a kind of indicator species, signaling the health—or lack thereof—of the ecosystem it inhabits. As its name suggests, the sage-grouse depends on sagebrush for food and nesting cover. A number of factors in addition to the juniper invasion have contributed to the bird’s shrinking habitat, including energy development, invasive weeds, drought, and urban expansion. But juniper’s impacts on grouse go beyond the loss of sagebrush: Grouse have evolved to give a wide berth to any tree more than four feet tall, because anything taller than a sage bush represents a potential perch for a predatory hawk.

When mature juniper cover reaches just 4 percent—picture taking a standard checkerboard and filling in just two and a half of the squares—sage-grouse abandon their leks.

“If you think back to the 1980s, you had juniper encroachment occurring, but a lot of these stands hadn’t fully matured yet,” says BLM wildlife biologist Travis Miller. “As the juniper is maturing and encroaching further, our habitat is getting choked. You go up to a lot of these table tops where we count the birds at these leks and you just look around, and you see it basically becoming woodland,” he says. A native of Burns, Oregon, a hundred miles east of the Badlands, Miller spent his high school summers working for his father, Richard Miller, an Oregon State University professor who did some of the foundational research on sagebrush and juniper fire ecology. In the late 1990s, the father-son team cored and aged the 1,600-year-old juniper near the Badlands.

Today the younger Miller is responsible for monitoring the sage-grouse population in the agency’s Burns district, where large areas of land are in the process of being treated to slow or reverse juniper encroachment. His assessment is not optimistic. “Either sage-grouse need to adapt to juniper, or they’re going to be gone,” he says. Miller’s grim conclusion is based on the sheer scale of the problem, and the current slow rate at which these treatments are being conducted. “There’s a lot of leks with a lot of juniper,” he says. “It’s a daunting task.”

One cold April morning, Miller sets out from Burns before dawn to complete an annual ritual: counting sage-grouse. Every spring, BLM staff conduct these counts at lek sites throughout eastern Oregon—often in areas where juniper is encroaching or has been treated—to monitor population trends.

The sagebrush steppe, which provides habitat to sage-grouse in 11 states in the West, has crossed an ecological threshold, Miller says. If the BLM and U.S. Forest Service—which share responsibility for managing habitat—leave the land alone, the ecosystem won’t return to the shrubby grassland that it used to be. Instead, it will become a juniper woodland with an understory of exotic annual grasses. Even if it were feasible to restore the historical fire regime that regularly scoured the grasslands, the land wouldn’t respond the way it once did, because aggressive invasive grasses have taken hold in Oregon’s rangeland. These interlopers—most notably cheatgrass (Bromus tectorum)—are quick to exploit open habitat left by fires, racing in before the native plants on which sage-grouse and other species depend have a chance to recover.

In Oregon’s eastern high desert—as in parts of Nevada, Idaho, and California—millions of junipers infest the once-grassy landscape. Young junipers have a tidy conical shape, and driving through the countryside here is like touring a haphazardly planted Christmas tree farm.

“We’ve been slowly losing our ranches to these green invaders for a long time,” says John O’Keeffe, president of the Oregon Cattlemen’s Association. He remembers spending one long-ago day, when he was about seven years old, helping his father direct the flow of a spring into a water trough for cattle. “My dad would carry a Polaroid camera with him when he did work around the ranch. About twenty years later, I found the photos he took that day, and if I hadn’t known the place I wouldn’t have recognized it because of all the juniper that had grown up.” The landscape was filling in. “I thought I’d inherited a ranch in the wrong part of the world,” O’Keeffe says. Ranchers with chainsaws have been clearing fifty or a hundred acres at a time for decades, fighting to keep their pastures open. But it’s been a losing battle.

In the past decade, however, the continuing decline of sage-grouse populations throughout the West has prompted the BLM to step up its war efforts. The agency has undertaken juniper control projects spanning tens of thousands of acres in Oregon alone, and millions of acres across the West. The goal is to reconnect isolated leks and safeguard the birds’ genetic diversity, as well as to protect the region’s dwindling water resources, and—somewhat ironically—to reduce the threat of out-of-control wildfires that has grown as these highly-flammable trees have proliferated.

Every site is different, but the most common method for removing juniper is called pile burning. It involves cutting down the trees, lopping off their branches, piling the debris on top of the stump, and burning the pile. Sometimes managers then reseed the land with native grasses to keep invasive cheatgrass from moving into the void left behind. In stands where encroachment has just begun, managers start prescribed burns to kill off young trees before they have a chance to mature.

Because juniper woodlands decrease the land’s productivity for cattle grazing at the same time that they consume valuable sagebrush wildlife habitat, ranchers are often eager to participate in efforts to control them. “We’re helping them address a concern that is as important to them as it is to anybody else,” says Sandy McKay of the Gilliam County Soil and Water Conservation District. “They’re making their livelihood off these lands and anything we’re doing that improves the health and productivity is a boon to them as well,” he says.

Large-scale eradication isn’t cheap, though. Depending on the method used, the cost can range from $200 to $600 an acre; the cost of clearing a one-mile-radius buffer around a sage-grouse lek starts at around half a million dollars. “You could spend all of your money for a year just to treat the area around one lek, and we have over a hundred active and inactive leks just in our district,” Miller says.

Ironically, the same federal wilderness designation that protects the old-growth junipers in the Badlands can also stand in the way of effective juniper management, as strict rules often prevent the use of the heavy machinery used to pile cut junipers in wilderness area; without machinery, the cost to treat a single lek can jump to a million dollars. Since the early 1990s, almost a million acres of BLM land in eastern Oregon have been designated “wilderness study areas,” tracts under consideration for permanent wilderness status.

Land managers have had to focus attention—and money—where it’s likely to have the most impact: on stands of young juniper growing in deeper soils that receive more moisture, where native grasses and sagebrush have a better chance of recovering, instead of mature stands where the ecosystem is likely too far gone to save. Several federal and state agencies offer grants to help ranchers tackle invasive juniper on private land. And the BLM coordinates juniper eradication on the vast swaths of public land it manages. One recently completed project in southeastern Oregon spanned 70,000 acres, and another, in the Burns area, aims to clear about 50,000 acres. Past monitoring has shown that the growth and productivity of herbaceous plants like grasses do in fact rebound after juniper is removed, and ranchers have reported increased flow in springs and streams.

Miller and I stand at a lek site northwest of Burns, high enough in the hills that the sun hasn’t burned off last night’s dusting of snow. Female sage-grouse have gathered to take in the spectacle of the displaying males, the yellow air sacs in their chests making incongruous popping sounds that carry in the quiet morning air. Two decades ago, says Miller, a healthy lek in this area might have attracted 40 males. Now he considers 20 good. This morning he’s pleased to count 19. On the surrounding hillsides, juniper woodlands sparkle with their overnight dusting of snow.

The birds don’t know or care about ecological thresholds, funding challenges, or anything else. “They just want us to cut juniper and treat invasive annual grasses. They want sagebrush steppe habitat, and they want us to get to it,” Miller says. “That’s what they tell me when I’m counting them. That’s what those early mornings do to you, you start talking to the birds.”

“We’ve been slowly losing our ranches to these green invaders for a long time.”

—John O’Keeffe, Oregon Cattlemen’s Association

Distribution of the Western Juniper, Eastern Oregon


Old-growth western junipers, like the younger, invasive segment of the species’ population, grow throughout eastern and central Oregon, western Idaho, and northern Nevada and California. But the dry, volcanic soil of Oregon’s Badlands Wilderness hosts an unusually large concentration of these old trees. Half a mile or so from the trailhead, Goodman-Campbell pauses to admire another one of her favorites. The tree’s arthritic-looking branches aren’t what most people would consider stately, but the textures of bark and lichen invite a closer look.

“This is a place that takes some time and attention to appreciate. It’s not like a waterfall—it’s not sexy. You’re not driving up to a viewpoint and looking out,” she says. “You have to look at the individual trees, look at the roots and the sand lilies and the moss.” What appears at first to be a barren, forbidding landscape is actually teeming with life.

The Badlands was once a popular spot for off-roading, compacting the soil and speeding erosion, and locals regularly cut down the ancient trees for firewood and decoration.

ONDA began campaigning to have the area designated as a federal wilderness area in the late 1990s. “It wasn’t one of the crown jewels of Oregon’s high desert, like Steens Mountain or the Owyhee, but it was valuable because it was close to Bend and provided an opportunity to educate people about wilderness by virtue of being so accessible,” says Bill Marlett, ONDA’s founding executive director.

In 2007, Senator Ron Wyden introduced a federal bill to grant wilderness status to the Badlands. The bill passed in 2009 and was signed into law by President Obama.

“People recognized that this was something valuable, something that needed protection and was threatened by people who would indiscriminately go in there and cut these trees down for firewood,” Marlett says.

Still, as the stump at the Flatiron Rock Trailhead—all that remains of a juniper that may have etched out a living there for more than a millennium—attests, these ancient trees still face threats. “I think some people don’t even realize,” says Goodman-Campbell. “They think, well, junipers are a weed, and I’m just cutting down this especially interesting-looking juniper.”

In its juniper-control efforts, the BLM gives old-growth trees a wide berth. And local conservation officials make sure ranchers understand how to identify old growth and why it should be left alone.

“You can just see the slow movement of time out here,” muses Goodman-Campbell, who’s now running for a seat in the Oregon state legislature to continue her quest to protect the state’s natural legacy. “Old things are more interesting than young ones. These are some of the oldest things in our state, and there’s something to be said for that. If we’re not saving some of the oldest living things in our state, what can we say about us as a society?”

Juniper challenges our ideas of what is natural. A seedling sprouting today could still be standing in the year 3000. Whatever the Western landscape looks like then, juniper will almost certainly still be part of it. Despite all the contradictions it embodies—native and invasive, loved and reviled, protected and targeted—one thing is sure: This tree is a survivor.

Map interactive by James Davidson

Rebecca Heisman

Rebecca Heisman is a freelance writer based out of Walla Walla, Washington. She worked in environmental education and wildlife biology before taking up writing, and especially loves birds. Follow her on Twitter at @r_heisman.

Kathryn Whitney

Kathryn Whitney is the former Photo Editor and Photographer for the California Academy of Sciences and bioGraphic, where she was able to combine her passions for science and photography every day. She is always ready for adventure, whether it’s outlasting a hailstorm while on assignment or galloping semi-wild horses across the Mongolian Steppe.

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