Mat-Su forests in poor shape, foresters say. Good news: Beetle infestation is waning

State and local officials are doing the best they can to keep ahead of the widespread spruce bark beetle infestation in the Matanuska Susitna Borough.

Beetles have killed hundreds of thousands of acres of commercially-valuable white spruce, and creating fire hazards as trees deteriorate and fall.

Some good news, however, is that the infestation appears to be slowing, based on recent data, state Division of Forestry and Fire Protection director Helge Eng told the borough assembly at its June 6 meeting.

Across Southcentral Alaska about 1.63 million acres of forests have been damaged by the beetles with big spikes in the late 1990s and another spike in 2018 and 2019. Things have leveled off since then and the rate of spread is now slowing, Eng said.

A lot of damage has been done. The Mat-Su Borough owns a relatively small share of forest lands in the borough, about two percent, about the same percentage for Alaska Native corporations. The state is the dominant owner with about 90 percent of the forest lands.

The borough’s forests are in poor condition, Emerson Krueger, a borough land and natural resource manager told the assembly. About 80 percent of the forest owned by the borough is in marginal or poor condition, he said.

The data hasn’t been updated in several years, so the percentage of marginal or poor trees is now undoubtably higher. There is little reason to believe that the condition of forest land owned by the state is any different, given the extent of the beetle-kill.

“Fifteen to 20 years ago we had healthy stand of mature spruce. Now most of it is overmature or dead,” Krueger said.

Meanwhile, the danger of the “fuel load” of dead wood is well known. The 2016 Sockeye Wildfire near Willow burned 7,000 acres and destroyed 40 structures. In 2019 the McKinley and Deshka fire burned 5,700 acres and destroyed 40 structures.

There are more fires likely because the chances are remote that significant funds needed to remove dead spruce across the Mat-Su region can be raised. An example of the costs of thinning and removing dead trees comes from the Sunset Fuel Break, an 11.3-acre parcel cleared as a fire break, and which cost $450,000.

What the state and borough are doing is engaging in timber salvage sales in specific areas to remove the “fuel load” in forests near communities or homes, Eng and Krueger said. The idea is that the damaged spruce has enough value left to pay the cost of clearing out the dead wood.s

The state’s land ownership is large enough, and with enough healthy trees, that regular commercial timber sales are held as well as the targeted salvage sales aimed at reducing fire hazards and improving forest health, typically through thinning of young trees.

However, the borough has had poor luck with commercial sales on its land, with only one sale held since 2011, Krueger said. In 2021 Mat-Su’s assembly authorized salvage sales, where the sale process is streamlined and the buyer negotiates a price.

Since 2021 five salvage sales on borough lands have been held with one of these now complete, involving 826 acres. One salvage sale still planned but not yet given final approval by the borough assembly is the Long Lake Salvage Sale involving 137 acres spread across five land tracts of 280 acres.

If the sale goes ahead the log trucks would use Nancy Lake Parkway to the Parks Highway at Mile Post 57. The logging would take about two weeks and produce1,000 cords of wood, according to information provided to the borough assembly.

Stephanie Nowers, a member of the assembly, asked why it is so difficult to do commercial timber sales. Eng, the state forester, said harvesters are challenged because the stands of healthy trees are geneally dispersed and broken up with the beetle-killed dead trees, which makes efficient logging a challenge.

Also, the lack of roads and distances trucks must go even where there are roads are impediments.

Krueger was asked how many acres of harvest is needed to supply local mills, which use wood for cabin kits and other products. The estimate is about 200 acres a year of cut, he said.

One aspect of the salvage sales is that they make superior moose browse, with a buffet of young growth.

One strategy being employed by the state and borough, the fuel breaks, is proving effective in enhancing public and property protection against fires. These are essentially strips of cleared or mostly cleared land that would provide a protective barrier against an advancing fire. They might not stop a fire in advancing but would slow it and provide places for firefighting equipment to be staged.

The Sunset Fuel Break, for example, involved 112 acres cleared by mechanical mean, or with heavy equipment, and another 32 acres with trees and brush removed by saw. This break protects Meadow Lakes and Houston in the borough.

Another is the Lynx Lake Fuel Brake along Lynx Lake Road, a 7.5 mile corridor, Another break is at Caswell.