A recent aerial survey is revealing that the 18-year battle to eradicate the mountain pine beetle from the Black Hills is slowing the pest's progress.
But despite reports by the U.S. Forest Service and other agencies that indicate that the beetles infested just 34,000 new acres in 2013 compared to as many as 67,000 acres as recently as 2011, U.S. Forest Service officials say they intend to press on in the war against a pest that burrows under the bark and sucks the life out of pine trees.
"We see encouraging declines in some areas, but we need to stay vigilant with this epidemic. We need to keep working with our partners to keep our forests green and more resilient to insects and damaging wildfire,” said Craig Bobzien, a forest supervisor.
The survey, which was conducted by the Forest Service, the South Dakota Department of Agriculture and Wyoming State Forestry Division, measures trees that were infected by pine beetles that left trees in the fall of 2012 and spread to new timber.
In 2009, beetles killed trees on 22,000 acres of the Black Hills; in 2010 it was 44,000 acres and in 2011 it was 67,000 acres, according to previous published reports.
Bobzien says 25,000 acres of national forest will be thinned this year to help stop the beetles from chewing their way through the forest.
"A lot of our work will be over toward Nemo," he said, adding that another stretch will be toward the border with Wyoming.
The survey also shows declines in mountain pine beetles in parts of Lawrence County and in Pennington County near the eastern edge of Lawrence County, according to Bobzien.
The beetles were originally discovered in the Black Hills in the late 1800s, according to the Black Hills Forest Resource Association website and was first dubbed “Black Hills Beetle."
Typical outbreaks last for five to 16 years, but the current outbreak started 18 years ago in 1996.
Ben Wuetke, forest programs manager for the association, said he's optimistic about the report, but he said the beetle battle must continue.
Other than the tree-thinning, Weutke said a "cut-and-chunk" approach has helped stem the beetle infestation, especially at Custer State Park. Infested trees are cut into about two-foot lengths, which cause them to dry out and starve the beetles.
"These initial signs of growth of the population tapering are hopeful," Wuetke said. But "it's a lot like taking antibiotics. If you stop now, it can come back in spades."