Stemming the tide

Christmas trees put to work on Flathead Lake



The dregs of the eggnog have been tossed and the hangover is drifting away. Now is usually the time to knock out the last chore of the holidays: dumping the Christmas tree.

There’s no shortage of environmentally negative or neutral ways to dump your tree, but Mark Lorang has come up with one that may help solve a chronic problem in the valley.

For decades, researchers at the University of Montana’s Yellow Bay Biological Station have warned of rapidly increasing nutrient levels in Flathead Lake.

Nutrients, mostly phosphorous and nitrogen, contribute to algae growth in the lake, which sucks oxygen from the water.

According to Lorang, a lakeshore erosion specialist for Yellow Bay, the lake may eventually reach a “tipping point” when oxygen levels decrease to a point where a chemical reaction causes more nutrients stored in the lake bottom to be released, causing more algae to bloom, and decreasing oxygen levels further. Over time, the lake would become murky with algae growth.

Lorang has been working for years to encourage low-impact solutions to erosion, one of the main contributors to the lake’s increasing nutrient levels.

In 2005, a few private landowners along the erosion-prone northern shore of Flathead Lake began installing “dynamic equilibrium beaches” composed of boulders, gravel and logs that together force waves to break earlier and dissipate their energy before they can take a bite out of the shoreline.

In the early 1990s, the U.S. Fish and Wildlife Service (USFW) proposed a two-and-a-half-mile seawall along the northern shore, but Lorang and others pointed out several problems with that approach, including the isolation of wetlands from the lake and accelerated erosion on neighboring land. USFW is now in the process of reviewing the dynamic equilibrium method for use along federally protected wetlands on the northern shore.

At the same time, PPL Montana, the power company that operates Kerr Dam at the southern end of the lake, has begun fulfilling the terms of its 1998 re-licensing agreement, which requires the utility to take steps to reduce lake erosion.

In December PPL announced a proposal to lower the lake’s water level by a foot next fall. If that proposal is approved by USFW, Lorang says, there will be a significant reduction in erosion during a time of year that produces a majority of the lake’s erosion-causing storms.

But neither beaches nor the lower water level will make much impact on erosion along the banks and at the mouth of the Flathead River.

And so PPL is paying for a novel method to help control erosion at those points, which is where the Flathead’s discarded Christmas trees come in.

Lorang, with the help of PPL Montana and Friends of Bigfork Schools, has been collecting Christmas trees that will be tied into bundles and deployed to minimize, and eventually reverse, erosion.

Recently Lorang helped conduct research along the erosion-prone banks of California’s Sacramento-San Joaquin River Delta, where bundled Christmas trees have been in place about five years.

The bundles, Lorang says, knock down boat wakes and wind waves, and allow mud and silt to build up behind them. In that recovered earth, cattails, willows and other riparian vegetation will be planted.

“Once plants get established,” Lorang says, “You defeat the erosion problem.”

Lorang is confident the same method will work along the banks of the Flathead River as well.

Although trees are being collected now, neither USFW nor Flathead County has yet approved the method for use on public land.

If the bundles don’t get approved for use this year, Lorang says, he will concentrate his efforts on private landowners who have already expressed interest in using the trees. Either way, Lorang plans to promote bundles for private use in the future.

He hopes to have this year’s bundles in place by March.

Paul Williams, a board member of the Flathead Lakers, a Polson-based nonprofit that advocates for water quality in the Flathead watershed, expresses confidence in Lorang’s work.

“He’s been involved in a variety of erosion-control techniques,” Williams says. “Every-thing he’s done has impressed me.”

Williams especially likes the idea of using Christmas trees.

“It’s waste material, and it’s organic,” he says.

A more common method for controlling erosion would be to dump rock along the river channel and at the mouth. But that method is costly, and just moves the problem.

“You’re fixing one spot, but making a big hole somewhere else,” he says.

During the 1950s, another method, far less organic than rocks or Christmas trees, was used to try to control erosion.

“If you go up and down the river above Flathead Lake, you’ll see a collection of beautiful old car bodies,” Lorang says.

Making the use of Christmas trees even more attractive is PPL Montana’s offer to pay nonprofit Friends of Bigfork Schools (FOBS) $3,000 for collecting the trees. Lorang is hoping for 1,000.

In the past, money raised by FOBS has been used to pay for new sports equipment, after-school programs and basic supplies for Bigfork schools.

“It’s not just a win-win,” says Mary Knoll, a founding member of FOBS. “It’s a win-win-win.”

Christmas trees—without decorations or tinsel—can be dropped off at the Crossroads Christian Fellowship Church on Montana 35, just north of Bigfork, anytime until Jan. 15, except between 8 a.m. and 1 p.m. on Sundays.

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