Beetle Mania


I’m sure you’ve heard about the bark beetles wreaking havoc across the forests of North America. And that the beetles have been killing pine trees at historic levels. But how’s Utah weathering the storm? People have talked about massive kill-offs south in Dixie National Forest and about some preventative efforts near Fish Lake in central Utah, but what about closer to the state’s most populous region, Salt Lake City? Is the Wasatch/Cache Forest immune to these outbreaks?

I’d listened to speculation that the Wasatch/Cache Forest was beetle resistant due to the type of tree they replanted with after being heavily logged in the second half of the nineteenth century and others told me that the Wasatch was simply protected, but when I related this bit of information to Jennifer Watt, Assistant Director of Environmental and Sustainability Studies at the University of Utah, her eyes widened and her head shook. Having co-authored papers on the subject she took pity on me. No, the Wasatch was not protected. In fact it may even be more at risk than other forests and not just from the beetles. Obviously I had a lot to learn about beetles so she started me with this, “You need to look into the spruce beetle.”

Sure enough the more I looked the more I found. Pretty much every tree in existence has a corresponding antagonistic beetle to go along. Historically these beetles have targeted stressed and unhealthy trees clearing out the stands and helping keep the ecosystem balanced, but recently they’ve gone off the charts. Dendroctonus rufipennis, or Spruce Beetle, is the number one killer of spruce all the way from Alaska down to Arizona and is currently devastating the spruce forests of Utah. Around the first warm spell every season theses beetles emerge looking for suitable host trees. Once found the females bore through the outer bark to create galleries in the phloem, soft tissue of the tree, in which to mate and lay eggs. These eggs hatch by August and, as larvae, continue eating the phloem, disrupting the tree’s flow of water and nutrients, which ultimately kills it. After two seasons they mature into adults and are ready to fly on to a new, living host.

In Utah spruce/fir forests are typically found above 9,000 feet and are considered high elevation, but they can and do exist much lower. They make up a huge portion of the Wasatch/Cache National Forest and are found in large numbers in the Cottonwood Canyons near the Salt Lake Valley.

Steve Munson, USDA Forest Entomologist and Leader of the Forest Health Protection Group of the Intermountain Region, has been dealing with Utah’s current spruce beetle outbreak since the mid-1990’s. He recalls when the Forest Service first found a spruce beetle outbreak in an area south of Brian Head Peak called Rainbow Meadows. They conducted surveys and identified the infested spruce. The timber was sold and the marked trees were removed. Soon more infested trees were found in Sidney Valley, east of Brian Head Peak. Once again the trees were marked for removal and additional thinning was planned for existing stands. This removal of timber never happened.


The sale of trees was appealed by the Southern Utah Wilderness Alliance. They argued that current logging practices would not prevent the spread of the beetle and would only lead to degradation of the environment. The Forest Service believed clearing out the infested trees and additional thinning of existing stands would be the end of the outbreak. Ultimately, the court sided with the Forest Service, but two seasons had gone by. (Follow up research proved stand thinning to have no effect on the spread of spruce beetles, but at the time it was unknown.) The epidemic had spread from the isolated stands into neighboring wilderness areas and Cedar Breaks National Reserve, where the policy was, and still is, to allow natural disturbances to run their course. Season after season the beetles flew. Brian Head Ski Resort was hit hard.

Brian Head Mountain Manager, Mac Hatch, related the nightmare. They lost all of their spruce, which made up 80% of their total trees. Huge swaths of forest were wiped out. Most of the mountain, once covered in green, was now bare. Afterward, with the help of the Forest Service, they removed the killed trees and replanted. The first big difference Mac noticed was the wind. After the trees were removed high winds arrived and downed several of their remaining healthy trees. Then, when winter came, lift closures due to high winds became common and still are. In addition to winds they have had to battle erosion. In nearly 20 years since, the replanted saplings have only grown to 4-6 feet tall. On a more positive note, it did open up more terrain for skiers and boarders. A look at Brian Head on Google Earth before and after 1994 shows the devastation clearly.larevalo_altasstn_0713_0021

From the Dixie National Forest the spruce beetle flew to the Wasatch Plateau where Jesse Morris first saw the results of this epidemic. A geography graduate student at the time, Jesse was amazed by the destruction. He was immediately intrigued about the possible differences between the current outbreaks and those before the West was settled. His research into the spruce beetle began. Using the absence of spruce pollen within soil samples taken from undisturbed alpine lakebeds within the Wasatch Plateau as a marker for outbreaks, Jesse began to gather data. Some evidence, going back 750 years, indicated epidemics occurred every 40 years. According to data a typical outbreak would kill 70% of the spruce within a stand. In the past 30 years certain outbreaks have killed more than 90% of the spruce. Looking to conduct more studies Jesse hopes to give the forest service a reference of natural activity from which to base future decisions on.

Talking with Steve Munson and other members of the Forest Health Protection Group I began to understand their role within Forest Service. Prevention and control of outbreaks along with restoration projects are within their scope. Vegetation management, pesticides, preventative measures for any disturbance, logging practices and fungi research; the list of interests goes on. They conduct surveys on not only insects, but also disease and invasive plants. For the beetles they rely heavily on aerial surveys. While they have been keeping tabs on the current spruce beetle outbreak, watching it make it’s way from the south to the center of the state and now into the Uinta and Wasatch/Cache National Forests, they have also been dealing with many other issues. Every member of the group I spoke to took their job seriously.

“Do you believe global warming is the key factor in the higher devastation of our forests when it comes to beetles?” I asked Steve Munson. He answered that was only part of it and that there were other elements that played a bigger role in the current state of forests in the west. First, we have huge stands of spruce trees across the West that are reaching the ages of 150-200 years old, which is exactly the age the spruce beetles prefer. Also, after logging we’ve replanted with the same species for much of the 20th century creating more same age stands that will mature at the same time. Second, we’ve had over 100 years of fire suppression, which has allowed trees to grow older, perpetuating a mono-species, allowing stand overcrowding and contributing to unhealthy and hazardous undergrowth (this is a huge area of concern in the Wasatch, not only for insects and disease, but for fire as well). And coming in at third is the warming climate. The mild winters and hotter summers have allowed the beetles to reproduce at rates twice as fast. Instead of taking two seasons to mature the spruce beetle is now doing it in one. Warmer climates also contribute to drought, which then stresses the trees and reduces their defenses, their ability to create pitch/sap, which may suffocate the beetles once they begin to bore.


On one level the Forest Health Protection Group does everything it can for prevention by spraying spruce trees with pesticides and using pheromone packets to dissuade the mountain pine beetle from choosing trees as a host, but these efforts are been confined to areas that have high value and have reasonable access. On such a large scale it’s not an easy task. Access, terrain, infrastructure and resources, are obstacles in the way of prevention. It’s not a pretty picture, but it’s one that Steve has come to accept. “Unfortunately, for another 150 years we can expect mass tree fatalities with only a few stands surviving… It’s a lesson for resource management going into the future to create a more diverse age class for high elevation stands of trees.” When asked if there was currently anywhere one could see management of a forest in a more diverse, healthy way Steve pointed me to Alta Ski Area.larevalo_wlfcrkbttle_0713_0041

“Once you manipulate a forest you can’t just let it be.” This statement came from Maura Olivos, Alta’s Sustainability Coordinator, as she explained Alta’s approach. It’s no secret that the forests near Salt Lake and Provo were heavily logged and mined. Both Big and Little Cottonwood Canyons were left denuded near the beginning of the 20th century. Replanting efforts were taken and the forests have rebounded. Yet with fire suppression and having the same age, same species stands they are just as susceptible to disturbances as any other forest in the West. Having always had a sense of responsibility for their environment, Alta created the Alta Environmental Center(AEC) in 2008. Since then the AEC has become key in directing their goals toward sustainability and addressing climate change. By initiating their vegetation plan they believe they are creating a healthier ecosystem that may weather many naturally occurring events. Through vegetation disturbance protocol, vegetation recovery monitoring, native seed collection, a native woody plant nursery, restoration efforts, forest management, weed control, beetle management, research and stewardship, Alta’s sustainability plan is tilting things in a positive way. Their efforts are definitely recognized by and partnered with the Forest Health Protection Group. Unlike the Forest Service alone, Alta and other ski resorts operating on public land have access to resources and infrastructure in place to help them heavily manage their areas. Similar to the Forest Health Protection group the AEC conducts surveys, but they are doing it on a more intimate level. They are constantly monitoring for disturbances on the ground, by sharing in the Forest Service’s aerial surveys and using new technologies. By using the GigaPan, stitching hundreds, if not thousands, of high-resolution images together to make panoramas of the area that can be zoomed in on, Alta started their GigaPixel project. From four different GPS plotted spots on the mountain they create panoramic images twice a year to be surveyed. Each image takes about one week of work to survey and has aided in the early detection of infestation and disease. At Alta and other ski areas they train their winter and summer crews to identify infestation.

When asked about the spruce and mountain pine beetle Maura replied, “We see about one or two trees infested by each beetle every year.” Whether that is a result of their current prevention efforts is unknown, but they are collecting data to create a baseline for the future. One or two trees infested a year would fall within the endemic levels of a normal ecosystem. However, as with most resorts, they take the bark beetles seriously. On the cool August morning that I happened to stop by they were removing an infested spruce. This particular tree was located in the north Rustler area, was identified three days prior and now was being removed and destroyed. At the base of the tree the holes where the beetles initially attacked the tree were mounded in hardened pitch. Maura peeled back the bark and found spruce beetles; dead adults, larvae and pupae.

Even with the surrounding resorts reporting infestation Maura remains optimistic. Alta doesn’t have as many trees as the other resorts and they have diversity. Since 2000 they have replanted a diverse set of trees ranging from 500 to 2000 each year. (Alta is having their annual tree-planting day September 7) Even if all their spruce were hit she believes they would have enough other species to help their ecosystem stay healthy.


A few days later I watched the sun set above a ghost forest of dead spruce in the Uinta National Forest. Wolf Creek Drainage was hit a few years ago. The forest service had to close the campground for safety reasons until the dead trees were removed. Reopened, it is not as attractive a destination as it once was. Surrounded by a faded spruce forest the tree-cleared sites sat open to the elements.  Wide tree stumps stared wide into the grey sky. A handful of beautiful trees in the main area had been preserved with the application of pesticides, but the surrounding forest was dead. Steve Munson estimates the overstory, canopy, at 95% killed. Patches of green winking out from the dead stands indicated a healthy understory. This could aid in recovery (some areas in the Wasatch Plateau that were hit in the 1990’s have yet to show any regeneration). East of the campground I watched mule deer idly graze in a meadow of grass beneath a wall of beetle-killed spruce. Further down the drainage a lone moose stripped green leaves from the brush.

With regard to our beloved Wasatch/Cache, Steve and everyone I spoke to acknowledged the spruce beetle along with other natural disturbances are here and it’s only a matter of time before the canyons of the Wasatch are hit hard. Driving down Little Cottonwood Canyon the other day I took note. We have a ton of spruce trees. Some are near the road, but the majo-rity are located in areas that would be extremely hard to access. Will we, the public, demand action and help fund preservation or will we let it go? Steve Munson is right. It’s a hard pill to swallow. Would it be easiest to just stand back and watch? I’m not so sure. Maura’s words come back to me and I feel a twinge of responsibility. “Once you manipulate a forest you can’t just let it be.”

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