It’s a difficult search for several reasons: The terrain is challenging – from the steeps of Vail Mountain to the forests of Ute Pass – and the work makes for long days. The forests are full of trees; and the normal signs the crew looks for aren’t always there, because of the state’s drought. But as mentioned, there are plenty to find, and once searchers find one, there are usually more in the neighborhood.
Colorado State Forest Service forester Kevin Williams is leading a crew on a survey of forests in Summit, Eagle and Grand counties. The duty of the team, composed of three Summit women and one Leadville woman, is to locate, mark and map trees infected by mountain pine beetles.
The state forest service team is working in partnership with local governments, ski areas and homeowners’ associations to keep at bay what is part of a natural cycle.
Mountain pine beetles, ant-sized black bugs that burrow into the trees, are endemic to the forests; they will always be there. They kill pines, however, and certain factors can exacerbate a break-out, causing the insects to spread through pine stands like wildfire.
“Each hit we find on a tree means about 70 to 100 eggs,” Williams said Oct. 9 on Vail Mountain. “You have 30 hits on a tree – that’s 3,000 bugs flying out the next summer looking for more trees. It doesn’t take long if nothing’s done. And then you’ve got big brown patches of dead trees.”
Looking for “hits’
The survey crew works four 10-hour days a week for seven to eight weeks in the fall. This year’s crew will work until late November, and past years’ crews have tromped through knee-deep snow to find beetle-infected trees.
“The good thing about doing it in the snow is you at least know where you’ve been,” said crew leader Katie Larson.
Larson, an Arapahoe Basin telemark skiing instructor and former Gore Range wilderness ranger, has spent four of the past five years helping the state forest service track down pine beetles, and surveyors have been trooping through national forests, towns and neighborhoods for two decades.
The crew marches through pine groves, whether gladed ski runs or county open space, and the surveyors use landmarks to “grid” their way around, inspecting every tree. They look for the tell-tale signs of pine beetle hits: rose-colored, popcorn-shaped pine pitch bubbling from a burrow hole, sawdust at the base of the tree or chipped bark where woodpeckers might have tried to get at beetle larvae.
If they find an infected tree, they check the trees in the immediate vicinity, as well. In July or August, the new generation of beetles mature and leave their hatching tree. They search for a new home nearby in a thick, sturdy tree that will make for good food. The females release a pheromone to invite the rest of the beetles once they’ve found a pine to burrow, and they release another pheromone when the tree is full to send bugs elsewhere.
The surveyors mark each tree with spray paint – a dot on the base (to identify the stump after the tree is cut down) and two Xs on the trunk. They also use a global positioning system to calculate the coordinates of each tree, and they mark the location on a map. Loggers will use the coordinates and map to find and fell the infected trees the next spring.
“It’s satisfying work,” said Randie McEntire, a carpenter who signed up for the job. “And it kind of opens your eyes.”
On this particular day, the group didn’t find too many hits around Vail’s Pride Express lift. But that’s not always the case. Vail Resorts was aggressive in removing trees discovered last year. Surveyors have discovered more hits in the vicinity of Keystone, especially across U.S. Highway 6 above the Summit County Landfill. Surveyors have found infected trees in the towns of Vail, Frisco and Dillon. Beetles have hit open space properties such as Summit County’s Lakeview Meadows.
Grand County is hardest hit of all, with some 28,000 acres in the Williams Fork drainage turning brown and dying from pine beetles burrowing into the trees’ water-carrying tissue and the fungus that lives on the beetles’ shell.
Looking in the backyard
The beetles are prevalent in national forest land. Looking at the forest east of the Henderson Mill in Grand County, the devastation the beetles can wreak is apparent – entire hillsides gone crimson. The U.S. Forest Service used to organize similar programs to control pine beetles, but budget cuts have eliminated those projects.
“And a lot of the chemicals they used to spray with you just can’t use anymore,” said Brian Lorch, a planner with Summit County Open Space.
But homeowners, especially those whose land abuts national forest, can take preventive measures. Professional contractors can spray uninfected trees to thwart beetle attacks, and services usually cost between $8 and $10 per tree. Foresters also can advise a landowner with a large enough plot on how to manage the trees; a diversity of ages and sizes of pines can keep beetles from killing the whole lot.
“It can get kind of depressing marking hundreds of trees to be cut down,” Larson said. “But it’s part of a natural cycle. This is what you get in a forest that’s ready to burn.”
Mountain pine beetle basics:
– Dendroctonus ponderosae Hopkins is a member of the family of “bark beetles,” completing most of its life cycle within trees.
– The beetle attacks and kills lodgepole, ponderosa, sugar and western white pines.
– Successfully infected trees can be identified by rose-colored pitch tubes on the trunk and by sawdust at the base of the tree. A blue stain in the sapwood caused by a fungus on the beetle’s shell is also an indication of infection.
– Beetles weaken and kill trees by burrowing (or girdling) trees through the trees’ water-carrying tissue and by clogging the same with their shell fungus.
– The beetles’ life cycle runs through a year, with adults emerging from trees in July or August, flying to and burrowing into other trees, then mating and hatching eggs, which develop over the next 10 months.
– The beetles are endemic; they will always be a part of pine forests.
– Outbreaks of beetles are affected by the age diversity of forests (food supply), trees’ ability to resist the beetles (influenced by stressors such as drought), beetle predators, temperature (it takes prolonged drops to about – 34 degrees Fahrenheit to kill beetles) and human controls such as spraying and forest management.
Partners against the pine beetle
Marking and mapping infected trees is only half the battle in the war against mountain pine beetles. Controlling the spread of the insect and the death they cause trees takes help.
Colorado State Forest Service surveyors finding infected trees don’t cut them down. There isn’t enough time and manpower, said Forester Kevin Williams.
“There’s only three of us foresters in the whole district,” Williams said. “So we partner with entities like Vail Resorts, get them the maps and information, and they’ll cut the trees down. With private landowners, like a homeowners association, we’ll help organize a timber sale.”
The state and federal governments pay for the projects. The partner groups submit invoices for the expenses of cutting down and removing trees. The state forest service then forwards invoices to its funding sources. The paper trail keeps the project alive, Williams said.
But the limited resources – financial, human and time – mean that not every infected tree is felled.
“We have to prioritize,” Williams said. “We ask, “Will this be effective? Will it make a difference? Will people treat trees in advance, or can we count on these people to remove the trees?'”
Williams said the project has met with success in towns such as Vail and Frisco, and Vail Resorts has been aggressive in removing the trees. Organizations that make it a priority make a difference.
“One of our criteria for a property is preserving visual corridors,” said Brian Lorch, a planner with Summit County Open Space. “We took out about 500 trees from Lakeview Meadows last year just to preserve that. But we did that to save probably 1,500.”
Setting money aside and participating in the project makes sense, said Vail Mountain snowmaking and trails manager Dave Tucholke. Thinning treed areas improves gladed skiing and removing infected trees (as opposed to cutting them down, debarking them and leaving the logs on the land) reduces fire fuel on the mountain.
“And dead trees have a huge visual impact,” Tucholke said. “We’re just trying to take a proactive approach to getting it under control. It’ll probably never be 100 percent, but we’re making a conscious effort to do the best we can.”
Editor’s note: Reid Williams is a staff reporter with the Summit Daily News.