Has this famous Northwest tree reached the point of no return?


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INDEX – It’s been six years since Bruce Albert witnessed the sudden, inexplicable death of dozens of western red cedar cedars on his property.


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The trees fell victim to an unknown comet in the span of one summer, and showed no signs of a deadly pest or pathogen. Nearby, Douglas fir, maple, alder, black cottonwood and more than a dozen surviving red cedar trees remain unaffected, if not thriving, to this day.

Albert is confused.

“There’s no pattern to that,” the 70-year-old said.

Similar symptoms were seen among red cedar trees throughout the Pacific Northwest.

For thousands of years, trees have been the pillars of stability and survival for the region’s forests and people. The blue-green scaly leaves decorated with small oval cones hanging from the drooping branches provide sustenance for elk when food is scarce during the winter. The striped wood, fibrous and tolerant, protected by a smooth layer of iconic red bark, wraps around a sturdy trunk that provides shelter for bears or useful material for humans.

Deepaks have cut countless trees throughout the region, but according to emerging research, they may never have been so prominently among the western red cedars or in such noticeable concentrations west of the Cascades mountain range.

Albert has been watching dozens of red cedar trees grow in his backyard since moving to Snohomish County in 1976, when heat waves, droughts and wildfires were less common amid the area’s lush fairways, forests and torrential rain.

Now, just beyond the next hill, the Bolt Creek fire has been burning since early September, A frightening harbinger of the West Side fires It comes as summer gets more intense and unpredictable.

Sick red rice may be the latest victim of the influx of extreme weather events.

Scientists, in their search for a cause, point to climate change, but to understand the nature and extent of the invisible threat looming on this beloved species, researchers need more time.

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Western red cedar, or Thuja plicata, is the largest tree in the Pacific Northwest and one of the oldest trees in western Washington.

It is one of the most common conifers here, evergreen, native to the Pacific coast of North America. The species first settled thousands of years ago in the rich soil of British Columbia. Tools made of red cedar have been found at Yuquot, a small settlement on Vancouver Island, dating back 4,000 years.

Now, it can be found in small orchards and old forests stretching from California to Alaska.

Sam Barr, a Samish tribesman and supervisor of the Stillagomish Tribe Historic Preservation Office, relies on the tree for his art, spirituality, and lifestyle.

“A lot of people refer to the cedar tree as being ancestral because it provides the essential gifts you need to survive,” Barr said.

He’s been harvesting materials from the tree for 14 years, using bark and wood to create art, tools, canoe paddles, and drums inspired by the traditional Salish Coast peoples.

Not only does the tree provide him the basic materials for construction and sculpture, but also a link to his ancestors and their history.

Red cedar was used by indigenous communities to build houses, canoes, totem poles, ropes, tools, utensils, bowls, blankets, baskets and more. The tree’s natural oils and buoyancy help make it water and mildew resistant, and therefore ideal for use on boats, rooftops, and clothing.

White settlers also found the tree useful for shingles, a continuing use today, as well as for building roofs and fencing, among other things, by residents of the Northwest across the region.

In the exacerbation of death, it is difficult for Bar to understand the loss of such essential species, especially those that are invaluable to the cultural heritage of First Nations, and essential 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 vibrant the tree is, and you can feel the fluids flowing up and down the trunk,” he said. “It is as if you can feel the heartbeat of a tree.”

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To study the potential differences between healthy red rice and those who are dying, researchers from Washington State University, Portland State University and Reed College collected nearly 30,000 hearts — small cylindrical cross-sections taken from inside the tree to check their age and health — from 280 red rice at 11 sites in Washington and Oregon. .

Early results indicate that dieback can cause red rice to grow.

Scientists have found that the species grows largely in unison, regardless of prior health conditions, until about seven years ago during the early stages of a statewide drought.

“So they grow less and less until they die,” said Henry Adams, a researcher at Washington State University.

Fellow and co-author Robert Andros said something happened after 2015 that made them respond very differently.

That year marked the beginning of an unusually hot and dry Washington weather that did not relent until 2018.

In the past 20 years, Washington has experienced seven of the 10 hottest years since 1895. In just the past decade, the state has experienced an unprecedented period of heat, with soaring temperatures booked by the unprecedented drought of 2015 and the infamous “heat dome” of 2021.

Between each bout of severe weather, the rice was given little time to recover.

Red rice can usually withstand seasonal drought or a single heat wave. But such events in quick succession can gradually impair a tree’s ability to retain water, grow, and protect itself from insects and disease.

Adams said red cedars are particularly sensitive to the weather conditions in May and June, because that’s when they’re preparing for the subsequent dry season.

Disruption of that cycle — like the unusually cold and wet spring weather Washington experienced earlier this year — could mean the difference between life and death.

“If there wasn’t a lot of moisture during that time, it would grow a lot less,” Andrews said. “And they will stop their growth so much earlier.”

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for years, Climate scientists have warned that global warming will destabilize the planet’s natural systems, pushing them beyond the tipping point into an irreversible feedback loop that eventually leads to mass extinctions and the collapse of entire ecosystems.

In 2008, British scientist Timothy Linton identified Nine planetary turning points, including melting or receding ice sheets in Greenland, western Antarctic Ocean and eastern Antarctica; breakdown or disturbance of ocean currents and monsoons in and around the Atlantic Ocean, West Africa, South Asia, and India; A significant death in the Amazon rainforest and boreal forests.

These tipping points are hard to predict, according to the report, because they arrive suddenly and can trigger or “skip” other tipping points. For the largest natural systems on Earth, the process could take millions of years.

But smaller local tipping points are expected to emerge as climate change, fueled by humanity’s consumption of fossil fuels, continues to worsen.

Researchers fear that western red cedar may have reached a tipping point.

“You don’t know where the edge is until you get past it,” Adams said.

If red cedars do, in fact, reach this point of climatic no-return, they face a horrific possibility: a situation in which vast swaths slowly but relentlessly fall victim to this death over the next decades or centuries, and species become extinct—or near it, by receding into Habitats located on the margins of their range suitable for living.

The Pacific Northwest has suffered a much greater death than this but almost exclusively at the hands of aggressive bark beetle infestations, a fatal disease or a fatal fungal infection.

While researchers believe that the cause of western red cedar’s death is ecological and abiotic, or nonliving, the exact cause and mechanisms for it—why trees respond in this way, are the most vulnerable, and what can be done to stop it—remain a mystery.

Perhaps the trigger is unobstructed sunlight. The soil may be dry. Maybe it’s low snow or stiff competition. The species may have migrated north into British Columbia, as was expected for many tree genera as the climate crisis alters their habitable habitats, often pushing them to higher latitudes and higher altitudes. It may be all of the above.

Each case requires a different treatment.

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aerial surveys Tree and Species Health Distribution has been conducted in Washington and Oregon by both states and the federal government for nearly 80 years. But it was only in 2017 that researchers began using a new label on their map: DC, short for “Dying Cedar.”

Surveys show that dieback is minimally scattered throughout the region but largely concentrated in urban corridors and lower elevations on the western side.

Joseph Hulbert, from Washington State University Forest Health Monitoring, is leading a project that collects data on the death of red cedar from a network of community scientists. The project collected about 1,800 data points from 250 contributors, helping Hulbert and other researchers to better understand what is happening on the ground.

In Cedar Creek Park in South King County, the remnants of a wilting red cedar tree were like a distress beacon as they slowly faded along with maples, hemlocks, and thriving fir.

Its branches were skeletal and bare, its crown colorless and its posthumously striped trunk studded with small holes carved by wood beetles.

“This guy is totally dead,” Glenn Koehler, a forest entomologist who studies the effect of insects on forest health, said in August.

Touch the soft bark before removing a small patch to check underneath. The tree lived in a healthy orchard surrounded by urban lanes in King County, had good access to sunlight and showed no signs of common tree killers.

Koehler said the losses were still under control if the death situation did not worsen.

If drought is the cause, Koehler said, reducing competition by loosening the substrate could help red rice get more water. But if it’s a combination of dryness and heat, the solution may require a more detailed approach.

Melissa Fisher Expert in the death of red rice A forest health specialist at the state’s Department of Natural Resources, said red cedar that goes through toffee appears to be exposed more often to sunlight. Trees under the canopy were often healthier than those receiving direct sunlight.

During drought, air bubbles drawn from dry soil can break the tree’s water column, causing that part of it to wilt or die. High temperatures and winds can cause the tree to dry out faster in the top canopy.

In western Washington and Oregon, reduced snow mass in spring may be associated with severe deaths.

While these clues are useful, it is too early to draw conclusions.

“We only have hypotheses about what’s going on,” Fisher said.

The timber should be harvested with caution, she said, and perhaps more red cedar trees should be left per acre harvested so they have a canopy to protect them.

“The bigger question is: How do you deal with these types now?”

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