They don't have the visual impact of a swarm of angry locusts or a sky blackened by grasshoppers. They don't kill people or wildlife.
They aren't particularly creepy by horror movie standards, and their work isn't even visible until a year or more after they finish.
Mountain pine beetles, black bugs the size of a kitchen match head, do their work quietly, methodically, leaving a path of destruction. They prefer pines and seek out ponderosa, Scotch and limber, but their favorite is lodgepole. Native to the forests of western North America, they have preyed on Colorado trees for generations, eating their inner bark and interrupting the life-giving transport of water and nutrients.
Their work had long been limited, a natural part of the cycle of life in Colorado's forests. The beetles did the most damage in trees already compromised by fire, injury or disease. But a decade ago, a series of natural forces combined to create the perfect conditions for a feeding frenzy never before seen.
"Their destruction is unprecedented in recent history," says Clint Kyhl, incident commander for the U.S. Forest Service's response to the pine beetle epidemic.
"Incident commander" and "epidemic" help illustrate the seriousness of the infestation in Colorado. Numbers drive the point home: The beetles have already destroyed lodgepole forests that cover 1.5 million acres, Kyhl says, adding that "by the time it is over, we expect it to have grown to 2 million acres."
If you estimate as Kyhl reluctantly will, when asked that each of those 2 million acres averages 500 trees, you're looking at a billion trees killed. That's more than 200 trees for every Coloradan.
Take a drive
Take a drive
The Forest Service believes beetles have killed trees in nearly all the lodgepole forests across the state, and that they'll probably kill nearly all of the state's large-diameter lodgepole pine forests in the next three to five years.
What does that actually mean to people around here?
That depends. If you don't travel much, you might not see any effects. Lodgepole pines usually grow at about 9,000 feet elevation or higher, so the thickest stands are found in parts of the state north and west of here. There aren't any lodgepoles on Pikes Peak or within the city limits of Colorado Springs.
And unlike other recent natural disasters like, say, the Hayman fire of 2002, the pine beetle's march isn't obvious to those who live outside its neighborhood. The historic fire that destroyed 138,000 acres less than 10 percent of the area impacted by the pine beetles gave off billowing smoke that obscured the horizon and painted sunsets blood red, for miles.
To really get a feel for the scope of the beetle epidemic, leave the region and drive toward Leadville or along Interstate 70 west of Denver, where sweeping stands of trees on hillsides are topped with red needles, the most obvious sign they are dying.
To understand the gravity of the potential loss, hike the Bierstadt Trail in Rocky Mountain National Park, a dark, cool path that snakes through a dense stand of 100-year-old, ramrod-straight lodgepoles.
To realize what some parts of Colorado will look like for the next few decades, visit the Heaton Bay Campground near Dillon Reservoir, where workers have already cleared dead trees so they won't fall on unsuspecting campers.
And though we're protected somewhat by our dearth of lodgepoles, there are a few pockets of pine beetle damage in ponderosa pines in Black Forest and along Ute Pass, says Colorado Springs forester Darrel Pearson.
"We see it occasionally in ponderosa," Pearson notes. "If it jumps on a large scale, which it can, from the lodgepole to the ponderosa, then we'll have a problem on our hands. Then it's like a runaway freight train."
Colorado Springs' forestry department regularly surveys trees in the region for both mountain pine beetle and Dutch elm disease. Trees attacked by pine beetles have to be removed. Others that might grow near the dying trees can be saved if they are sprayed with pesticide.
In Woodland Park, a community that covets its densely packed forests, the fight against the beetles has gained urgency. The Colorado State Forest Service office there is helping homeowners scout for beetles. (If asked, state forest service officials will do the same for homeowners all over Teller, Park and El Paso counties.)
And last week, the U.S. Forest Service started cutting down and chipping ponderosas on 150 acres east of Woodland Park in the Sunny Glen subdivision. The project was designed to remove "brood trees," which harbor the pine beetle larvae through the winter months.
"We walk strips on a property, looking for pitch tubes," state forester Andy Pascarella says, referring to the popcorn-shaped resin masses that form where the beetles tunnel. "If we find a tree with beetles, it has to go. And whether that tree indicates others on the property have beetles depends on the wind what way the wind was blowing when the beetles flew."
How it happens
How it happens
Pine beetles have a one-year life cycle. Their methodical attack begins in late summer, when adult beetles leave the trees they have killed and fly to new ones. Females look for new targets lodgepoles at least 6 inches in diameter and tunnel under the bark. Males follow, and the beetle pairs mate and produce eggs.
After the eggs hatch, the larvae dig tunnels to their new homes and spend the winter under the bark. In late July, the new generation emerges and it starts all over again.
It's an efficient process, says Kyhl.
"We have seen trees with as many as 1,000 beetles in them," he says, "but it only takes a handful of beetles to kill a tree."
In the past, the beetles were kept in check by natural conditions. Many couldn't survive extremely cold winters. Their ability to harm trees was diluted during summers with plentiful rainfall, which kept the trees strong and resilient.
But then, Kyhl says, drought, climate change and forest conditions combined to create a beetle's paradise.
The story goes back more than a century. Newcomers to Colorado in the late 1800s and early 1900s were amazed at the wealth of riches they found here. Vast green forests yielded seemingly endless supplies of firewood and timber for homes, mines and towns.
The new residents weren't great environmentalists. They started fires to clear pastures, carelessly let campfires sweep through forests, and chopped and cleared trees without much thought to the future. Wood was free and plentiful.
Logging and fire cleared the forests, but the trees, especially the lodgepoles, were good at regeneration. With a clear view of the sky, new trees took root.
Today, those trees, all grown up, fill the Routt, Arapaho, Roosevelt and White River national forests. They sweep from Grand Lake to Kremmling, Steamboat Springs to Winter Park, and they also cover large areas around Dillon, Vail, Glenwood Springs and Aspen.
The forests are thick, after decades of fire suppression.
"We created a forest filled with trees that are all the same age," Kyhl says. "Now, all those trees are 100 to 120 years old and are all the size and age of trees the bark beetles like to eat."
Add to that a couple other factors, Kyhl says.
"Along came an extended period of drought, and in the last six to seven years, a really extensive drought. With drought, the tree doesn't have the moisture to defend itself.
"And then add the other factor mild winters and you've got that perfect storm."
It sounds like Colorado's soon to be transformed into a vast, treeless landscape. But Kyhl's optimistic.
"I've dedicated my life to the forest and trees," says the 47-year-old. "This will be a huge change, but it really is nature's way of regenerating. This is our chance to set up a healthy forest for future generations."
John Stansfield also feels hopeful. Stansfield, from Larkspur, has been a relentless advocate for the environment across nearly four decades. At 60, he's an active member of the Sierra Club. He also founded the Central Colorado Wilderness Coalition, a group that works to raise awareness of potential wilderness areas in the central part of the state.
Stansfield recently returned from a trip in Yellowstone National Park, where he cross-country skied through forests that have regrown since the massive 1988 fires.
"Traveling through Yellowstone 20 years after the fires there, in the predominantly lodgepole forests, I could see the indomitable spirit of regeneration," he says. "There's a lot of hope in that natural process."
Stansfield works as a storyteller, and he's developed a storytelling program and a book around the life of one of his favorite characters, Enos Mills, a naturalist at the turn of the 20th century remembered as the "father" of Rocky Mountain National Park.
Mills spent his days exploring the forests of the park, recording much of what he saw in his journals. The fact that today's mature trees were seedlings when Mills saw them isn't lost on Stansfield.
"He was observing the forests and watersheds 100 years ago, seeing whole watersheds that were 10 percent forested, 15 percent forested," Stansfield says. "He saw some incredible devastation. But he also had faith in the natural processes."
Today, stewards of Colorado's forests are working to make sure regeneration and recovery processes proceed in the right direction.
U.S. Rep. Mark Udall, D-Eldorado Springs, has sponsored national legislation to provide the Forest Service with funds to thin trees and reduce fuel loads, and to provide incentives to landowners to remove dead or dying trees. He has worked on the pine beetle issue for years, and recently sponsored a workshop on hazard mitigation efforts and resources to help hard-hit communities.
"This issue has helped many realize that our forests are unhealthy and that we need to better manage them," Udall recently wrote in an e-mail to the Independent. "That management should include new entrepreneurial approaches, such as finding ways to use the wood for beneficial uses like energy production. This can also help make the forests more healthy and resilient and better able to respond to an insect epidemic of this scale."
Gov. Bill Ritter has created a multi-agency Colorado Forest Health Advisory Council, saying "the time has come for a unified, coordinated and aggressive action plan."
Comprised of representatives from city, county, state and federal governments, and the woody biomass industry, water suppliers, conservation groups and sportsmen, the council is working on a number of measures. They include creating community wildfire protection plans, considering incentives to reduce forest treatment costs, continuing a forest restoration grant program, and looking at long-term strategies for a healthy forest.
A whole new forest
A whole new forest
In its response to the beetle epidemic, the Forest Service has three priorities, Kyhl says.
Mitigating the danger of large-scale wildfires and the damage they could cause people, property and the state's watershed. "We already know that a large-scale fire can increase sedimentation in the watershed," he says.
Dealing with hazardous trees. "Removing the trees is a big issue for us, especially as the trees die and start falling over the next several years. Those trees could close trails or roads, or fall on power lines. We may or may not have a fire, but we know those trees are going to fall down."
Dealing with the next forest. "We want to ensure that we have a healthy, resilient forest for the future."
What will that future hold? Like Stansfield, Kyhl looks to Yellowstone.
"The lodgepole is a prolific seed producer," he says. "We can expect a huge flush of trees, and probably more aspen, too. And we will still have the spruce and fir trees that haven't been affected."
That's comforting to Coloradans like Becky Wegner, whose family often heads to the outdoors. Wegner has worked as a forester and now operates Mountain High Tree Care, a tree-care company in Colorado Springs.
Wegner says she looks at the epidemic as a time of change.
"For the rest of our lives, the forest where we go skiing and hiking in the high country will be different," Wegner says. "But it won't be devoid of growth. There's a whole new forest underneath."
In the meantime, she's bracing herself for losing some of the state's historic trees. Wegner is a member of the Colorado Tree Coalition, a nonprofit forest advocacy group based in Fort Collins. The coalition keeps track of what it calls Champion Trees, the largest of each species in Colorado.
Among its 700 champions are three venerable lodgepoles, including a 74-foot giant in Rocky Mountain National Park. It probably won't survive the beetles' attack.
Was it one that naturalist Enos Mills met in his ramblings? No one knows for sure. But if he did, it was a seedling with a life of struggle ahead of it.
"It is almost a marvel that trees should live to become the oldest of living things," Mills wrote in The Story of a Thousand-Year Pine. "Fastened in one place, their struggle is incessant and severe. From the moment a baby tree is born from the instant it casts its tiny shadow upon the ground until death, it is in danger from insects and animals."
Still, Mills believed the life of a tree was a worthy one: "Trees have adventurous lives from their seedling days to battered old age."
The bite and the bark
The mountain pine beetle, Dendroctonus ponderosae, is native to the forests of western North America.
It's about the size of a large match head, and can be distinguished from other bark beetles by the shape of its hind wing cover, which is gradually curved.
Its predators include woodpeckers, flies, wasps and other types of beetles. Some predators capture the beetles outside the trees; others destroy the larvae within the trees.
Normal flight period starts in July, and ends when temperatures drop below freezing.
The beetles carry mycangia, shallow pits that carry blue stain fungi. The fungi penetrate the wood, and, yes, stain it blue.
Sources: Colorado State Forest Service, U.S. Forest Service
In Colorado, lodgepole replaces ponderosa on the west side of the Front Range. It's the most common forest tree in Wyoming's Yellowstone National Park and also grows in South Dakota's Black Hills.
The lodgepole is a slender tree that can grow to 80 feet. It can grow at elevations from 6,000 to 9,800 feet, but is found most commonly at around 9,000.
The wood of the lodgepole is moderately strong. It was valued by Plains Indian tribes and settlers in the West; today, it's used in the construction of log cabins, posts and poles, siding and rustic furniture.
Noted naturalist Donald Culross Peattie called the lodgepole pine "one of the most curious and significant of all western trees ... It is at the same time a forest weed and a commercial timber crop, a tinder box in case of fire and a phoenix after it."
Source: The Native Trees of the Southern Rocky Mountains: From Yellowstone to Santa Fe by Stuart Wier
Signs of beetle victory
Popcorn-shaped masses of resin, brown, pink or white, called "pitch tubes," on the trunk where the beetles tunnel in.
Boring dust in the crevices of the bark and on the ground next to the tree base.
Evidence of woodpeckers feeding on the trunk.
Needles that turn yellow to red throughout the entire tree crown, usually from 8 to 10 months after the beetles attack.
Sources: Colorado State Forest Service, U.S. Forest Service