INDEX — It’s been six years since Bruce Albert witnessed the sudden and inexplicable death of a dozen Western red cedars on his property.
The trees fell victim to an unnamed criminal over the course of a single summer and showed no signs of deadly pests or deadly pathogens. Nearby, Douglas firs, maple, alder, black poplar, and more than a dozen surviving red cedars remain unaffected, though undeveloped to this day.
Albert is stunned.
“There’s no pattern to it,” said the 70-year-old.
Similar symptoms have been seen among red cedars in the Pacific Northwest.
For thousands of years, trees have been pillars of stability and survival for the region’s forests and inhabitants. Scaly, green-blue leaves decorated with small, oval cones hanging from drooping branches provide food for deer when food is scarce in winter. Fibrous and forgiving striated wood, protected by a soft layer of iconic red bark, wraps a solid trunk that offers shelter for bears or useful material for humans.
Rollbacks have knocked down countless trees across the region, but they’ve never been more pronounced, perhaps in such remarkable concentrations among Western red cedars or west of the Cascades, according to emerging studies.
Albert has watched dozens of red cedar trees grow in his backyard since he moved to Snohomish County in 1976.
Now, just beyond the next hill, the Bolt Creek fire has been burning since early September. a frustrating harbinger of west coast fires The summers come as they become more and more severe and unpredictable.
Sick red cedar trees may be the latest victims of the influx of extreme weather events.
As scientists look for a cause, they point to a changing climate, but researchers need more time to understand the nature and extent of the invisible threat looming over this beloved species.
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Western red cedar, or Thuja plicata, is the largest tree in the Pacific Northwest and one of the oldest in Western Washington.
Native to the Pacific Coast of North America, evergreen is one of the most common conifers there. The species first took root in the rich soils of British Columbia thousands of years ago. Tools made of red cedar found in Yuquot, a small settlement on Vancouver Island, date back 4,000 years.
It can now be found in young groves and old forests stretching from California to Alaska.
Sam Barr, a Semitic citizen and chief of the Stillaguamish Tribe’s historic preservation office, relies on the tree for his art, spirituality, and lifestyle.
“Many people call the cedar tree grandparents because it provides essential gifts you need to survive,” Barr said.
Inspired by the traditional Coast Salish peoples, art has been collecting wood for 14 years, using bark and wood to create tools, canoe paddles and drums.
The tree not only provides him with the necessary materials to build and carve, but also provides a link with his ancestors and their history.
Red cedars were used by Indigenous communities to build houses, canoes, totem poles, rope, tools, utensils, bowls, blankets, baskets, and more. The wood’s natural oils and buoyancy help it resist water and rot, making it ideal for use on boats, roofs and clothing.
White settlers also found the tree useful, among other things, by Northwesterners in the area for shingles, a use that continues today.
If the return worsens, it’s hard for Barr to understand the loss of such an important species, especially one so valuable to First Nations cultural heritage and fundamental to the history and growth of the region.
“When you peel the bark off the tree and put your hand on the bare trunk, you can feel how alive the tree is, you can feel the fluids flowing up and down the trunk,” he said. “It’s almost like you can feel the tree’s heartbeat.”
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To examine possible differences between healthy red cedar trees and those experiencing dieback, researchers from Washington State University, Portland State University, and Reed College collected about 30,000 seeds, which are small, cylindrical sections taken from the inside of the tree to examine their age and health. 280 red cedar trees at 11 sites in Washington and Oregon.
Early findings suggest that dieback may cause red cedar growth to take off.
Scientists have found that, up to about seven years ago, in the early stages of a nationwide drought, the species largely grew in harmony, regardless of previous health conditions.
“They grow less and less until they die,” said WSU researcher Henry Adams.
His colleague and co-author Robert Andrus said something happened that caused them to react very differently after 2015.
That year marked the beginning of unusually hot and dry weather in Washington that didn’t subside until 2018.
In the last 20 years, Washington has experienced seven of its 10 warmest years since 1895. In the last decade alone, the state has endured an unprecedented period of heat that was booked by an unprecedented drought and the notorious “heat dome” in 2015, with rising temperatures. year 2021.
Between each extreme weather event, the cedar trees were given little time to recover.
Red cedars can normally survive a seasonal drought or a single heat wave. But such events in rapid succession can gradually weaken a tree’s ability to retain water, grow, and protect itself from insects and disease.
Adams said red cedar trees are particularly sensitive to climatic conditions in May and June because they are preparing themselves for the next dry season.
Disrupting this cycle – like the unusually cold and wet spring weather Washington saw earlier this year – could mean the difference between life and death.
“If there isn’t a lot of moisture during this time, they will grow a lot less,” Andrus said. “And they will shut off their growth much sooner.”
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for years Climatologists have warned that global warming will destabilize the planet’s natural systems and push them beyond a tipping point into an irreversible feedback loop that eventually leads to mass extinctions and the collapse of entire ecosystems.
British scientist Timothy Lenton in 2008, nine planet tipping pointsincluding the melting or retreat of ice sheets in Greenland, the western Antarctic Ocean, and East Antarctica; subsidence or disruption of ocean currents and monsoons in and around the Atlantic, West Africa, South Asia and India; and the great dead in the Amazon rainforest and boreal forests.
According to the report, these tipping points are difficult to predict because they occur suddenly and can even be triggered or “hit” by other tipping points. For the world’s largest natural systems, the process can take millions of years.
But as climate change fueled by humanity’s fossil fuel consumption continues to worsen, smaller, local spill points are expected to emerge.
Researchers fear that Western red cedars may have reached a tipping point.
“You don’t know where the border is until you’ve crossed it,” Adams said.
If red cedar trees have indeed reached this climatic point of no return, they face a dire prospect: vast areas fall slowly but inexorably over the next decades or centuries of this reversal, and the species goes extinct, receding into habitats bordering on their Habitable ranges – or also close to him.
The Pacific Northwest has suffered far greater deaths than this, but almost exclusively at the hands of an aggressive bark beetle infestation, deadly disease, or deadly fungal infection.
While researchers believe the reason for Western red cedar wood’s return is environmental and abiotic or non-living, the exact cause and mechanics of it—why trees react this way, the most vulnerable, what can be done to stop it—remains an issue. mystery.
Maybe the trigger is unobstructed sunlight. Maybe it’s dry soil. Maybe a low profit package or too much competition. Perhaps the species is migrating north to British Columbia, as predicted for several tree genera, as the climate crisis has changed their habitable habitat and often pushed them to higher latitudes and higher altitudes. Maybe it’s all of the above.
Each condition requires a different treatment.
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aerial surveys For nearly 80 years, tree health and species distribution has been conducted by both the states and the federal government in Washington and Oregon. But it was only in 2017 that researchers started using a new label on their maps: DC, short for “Dying Cedar.”
Surveys show that the return is sparsely distributed over the entire region, but is largely concentrated in the urban corridors and low elevations on the west side.
Joseph Hulbert of WSU Forest Health Monitoringis leading a project that collects data on red cedar wood return from a network of community scientists. The project collected nearly 1,800 data points from 250 participants, which helped Hulbert and other researchers better understand what’s going on from the ground up.
At Cedar Creek Park in South King County, the pale remains of a young red cedar stood like a danger sign as it slowly rotted alongside the thriving maples, hemlock, and firs.
Its branches were skeletal and bare, its crown colorless, and its striped trunk adorned with tiny holes carved by wood-drilling insects after death.
“It’s completely dead,” said Glenn Kohler, a forest entomologist who studies the impact of insects on forest health, in August.
He touched the soft crust before removing a small patch to check his bottom. The tree lived in a healthy grove in King County surrounded by urban corridors, had good access to sunlight, and showed no signs of widespread tree killers.
Kohler said the losses are still manageable if the return doesn’t worsen.
If drought is to blame, reducing competition by thinning the substrate could help red cedars take in more water, Kohler said. But if it’s a combination of drought and heat, the solution may require a more specialized approach.
Melissa Fischer, an expert on the return of red cedar and a forest health expert with the State Department of Natural Resources said red cedar trees that have undergone relapse are exposed to more frequent sunlight. Trees under canopy were healthier than trees in direct sunlight.
During drought, air bubbles drawn from scorched soil can break the water column of a tree, causing that part to wilt or die. High temperatures and wind can cause a tree to dry out faster in the upper canopy.
In western Washington and Oregon, low spring snowpack may be associated with severe cases of returns.
While these tips are helpful, it is too early to draw any conclusions.
“We only have hypotheses about what’s going on,” Fischer said.
Timber harvesting should be done carefully, and perhaps more red cedars should be left for each acre harvested so that they have a canopy to protect them.
“The big question is: How do you currently manage this genre?”
