From The Denver Post (Bruce Finley):
New research shows forests not bouncing back from fires as quickly, which could lead to erosion and strains on drinking water
The U.S. Forest Service and Boulder County have begun a $6.5 million emergency push to try to stabilize slopes here before hard summer rain. It’s an immediate fix for what research indicates could be a long-term problem…
In Washington, D.C., Democratic Sen. Michael Bennet and Rep. Joe Neguse are pushing legislation to deploy tens of thousands of workers to thin western forests before fires break out — a technique Boulder County land managers have used repeatedly over the last decade. Federal land managers, meanwhile, said they’re evaluating whether to replant and how much in an effort to promote at least partial recovery from a wildfire…
Focus on forest health
Wildfires played key roles in forming forests over thousands of years, bringing balance and diversity. But natural cycles were distorted by decades of humans aggressively suppressing fire, which is still a priority in Colorado and other western states. The resulting tree density, along with high temperatures and aridity, led to last year’s record-breaking megafires in California and Colorado.
“In many recently burned areas, trees aren’t reestablishing. We’re seeing this especially in wildfires that burned in Ponderosa pine forests,” said Tony Cheng, director of the Colorado Forest Restoration Institute and professor of forest and rangeland stewardship at Colorado State University.
Cheng recently testified in Congress, warning that forest fires are releasing more carbon into the atmosphere, that forest recovery may take centuries — if it happens at all — and that the United States’ capacity to sequester carbon is diminishing.
“If recent research is providing insight into the future, the prospects are low for forests to return to what people were used to seeing,” Cheng told The Denver Post. “Forest cover could be sparser, trees would be replaced with shrubs and other plants, the wildlife might be different, and the water-holding and filtering capacity of forests would be altered for a long time.”
A University of Colorado study published in February tracks with his assessment and blames climate warming. A 2017 study using data from 1,485 burn sites found increasingly unfavorable conditions for forests to regenerate throughout the Rocky Mountain West.
And northwest of Colorado Springs, the 70-square-mile core of the 214-square-mile scar from the 2002 Hayman fire shows how severe burning can reduce a towering 200-year-old Ponderosa and Douglas fir forest to grasses and shrubs two decades later.
Fighting to ‘keep the soil on the slopes’
Up on the blackened mountainsides between standing dead pines, orange-vested contractors recently were scoping sites to install 30 small dams and a pond to try to keep soil, crucial for new growth, from eroding.
Ground crews sawed into the pines, leaving roots in place. Amid a staccato thudding, red helicopters crisscrossed overhead, hoisting cut trunks using dangling hooks and hauling them into massive piles. A tractor-sized grinder turned the trunks to tons of mulch, which helicopters hauled in nets and dropped over severely scorched slopes six inches thick.
This emergency effort must stabilize the burned terrain as quickly as possible, Glowacki said, adding, “Our role in this is to keep the soil on the slopes.”
But by May 21, only 200 acres out of 1,800 acres prioritized in the project had been covered. The grinder had broken.
If scorched slopes remain barren, hard rain likely will cause flooding, possible slides and wash sediment into Geer and Plumley creeks, which flow into Lefthand Creek, the drinking water source for communities north of Boulder.