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Dead Trees Tell No Lies: The Electron Mudflow · Street Smart Naturalist

• 0:01
  SPEAKER_00: Greetings,
• 0:02
  SPEAKER_00: this is David B.
• 0:03
  SPEAKER_00: Williams and the podcast of my newsletter,
• 0:06
  SPEAKER_00: The Street Smart Naturalist,
• 0:08
  SPEAKER_00: Explorations of the Urban Kind.
• 0:11
  Every week I share my observations and adventures with the
• 0:14
  human and natural world
• 0:15
  SPEAKER_00: around Seattle,
• 0:17
  SPEAKER_00: Puget Sound,
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  SPEAKER_00: and the Pacific Northwest.
• 0:20
  SPEAKER_00: Today's episode highlights some amazing tree ring research.
• 0:25
  SPEAKER_00: To learn more about my work, please go to my website, geologywriter.com.
• 0:29
  You will also find a link to my Substack newsletter and my
• 0:32
  previous five years of
• 0:34
  SPEAKER_00: newsletters,
• 0:35
  SPEAKER_00: as well as images tied to this week's episode.
• 0:38
  SPEAKER_00: Thanks again for joining me on this adventure,
• 0:41
  SPEAKER_00: and welcome to Podcast 61 of the Street Smart Naturalist,
• 0:46
  SPEAKER_00: Dead Trees Tell No Lies,
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  SPEAKER_00: The Electron Mud Flow,
• 0:50
  SPEAKER_00: February 5,
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  SPEAKER_00: 2026.
• 0:55
  SPEAKER_00: In October of 2023,
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  I published a newsletter about scientists using tree rings to
• 1:01
  date the Seattle
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  SPEAKER_00: fault.
• 1:03
  SPEAKER_00: I wrote,
• 1:04
  SPEAKER_00: It is a tour de force and beautiful example of science,
• 1:07
  SPEAKER_00: taking a unique set of features and combining technology with old school,
• 1:11
  SPEAKER_00: out in the field,
• 1:12
  SPEAKER_00: mucky,
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  SPEAKER_00: muddy detective work to answer an essential question.
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  SPEAKER_00: Two members of the group,
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  SPEAKER_00: Pat Pringle and Brian Black,
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  SPEAKER_00: along with USGS volcanologist Jim Valance,
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  SPEAKER_00: have done it again.
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  SPEAKER_00: They have solved an essential question via dendrochronology.
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  SPEAKER_00: They have pinpointed the date of the electron mudflow to the year 1507.
• 1:37
  SPEAKER_00: If you're not familiar with this epic mudflow,
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  it's one of as many as 50 massive debris floods that have
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  rocketed down the slopes
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  SPEAKER_00: of Mount Rainier
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  SPEAKER_00: also known as lahars,
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  SPEAKER_00: a Javanese word for a hot volcanic mudflip,
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  SPEAKER_00: which was introduced into English in 1922.
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  SPEAKER_00: They are some of the most destructive geologic events in our region,
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  SPEAKER_00: typically started by an eruption.
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  SPEAKER_00: More on that later.
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  Lahar begins with a massive avalanche and rockfall when
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  magmatic heat melts glacial
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  SPEAKER_00: ice,
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  which mixes with hydrothermally weakened rocks to form a
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  concrete-like slurry.
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  SPEAKER_00: As the mire and muck descends,
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  it can obtain speeds in excess of 125 miles per hour as it
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  scours valleys,
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  SPEAKER_00: climbs ridges and hills,
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  SPEAKER_00: and assimilates whatever lies in its path.
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  SPEAKER_00: ranging from animals to massive boulders to old-growth trees.
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  SPEAKER_00: The debris eventually slows down when it hits the lowlands,
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  but can still be traveling 40 miles per hour dozens of miles
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  from the mountain's
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  base and leave behind hundreds of square miles covered in a
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  blanket of death,
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  SPEAKER_00: desolation,
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  SPEAKER_00: and destruction.
• 2:54
  SPEAKER_00: Dang!
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  SPEAKER_00: Armed with the knowledge of these potentially deadly natural hazards,
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  Emergency preparedness people have been working to aid
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  communities in the path of Lahars.
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  SPEAKER_00: For example,
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  SPEAKER_00: several years ago,
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  a friend of Marjorie's bought a house in the small town of
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  Orning on the Puyallup
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  SPEAKER_00: River.
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  SPEAKER_00: On the day they moved in,
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  SPEAKER_00: it was sunny,
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  SPEAKER_00: and they realized they had a wonderful view of Mount Rainier.
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  SPEAKER_00: The next day,
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  SPEAKER_00: they received a Welcome to Orning packet,
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  SPEAKER_00: which contained coupons and other items,
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  SPEAKER_00: including a Lahar escape plan.
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  Not a bad idea to have when your town rests atop 20 feet of
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  debris deposited by the
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  SPEAKER_00: electron mudflow.
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  SPEAKER_00: Geologist Dwight Crandall first described the electron in 1963.
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  He wrote that it consisted of an unsorted mix of rock fragments
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  in a matrix of
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  SPEAKER_00: purplish-gray clay sand with boulders up to two feet wide.
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  The thickest deposits were 26 feet deep and varied considerably
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  depending on the
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  SPEAKER_00: original surface topography.
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  SPEAKER_00: Within the deposits,
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  he recovered a wood sample radiocarbon dated to 530 plus or
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  minus 200 years.
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  Crandall could find neither source nor a trigger,
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  in particular an eruption.
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  SPEAKER_00: Thirty years later, geologist Pat Pringle was driving an ording.
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  SPEAKER_00: when he saw a construction site with buried trees,
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  SPEAKER_00: most,
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  SPEAKER_00: or at least their stumps,
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  SPEAKER_00: still stood upright.
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  SPEAKER_00: He was able to cut sections out of about a dozen long-dead Douglas firs,
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  SPEAKER_00: bring them into a lab,
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  SPEAKER_00: and age-date them.
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  SPEAKER_00: One of them, ELE001, had a good set of rings showing that it died between
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  SPEAKER_00: 1476, and 1522.
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  SPEAKER_00: The dates confirmed Crandall's time estimate for the electron mud flow,
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  SPEAKER_00: but Pat wanted a more precise date.
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  SPEAKER_00: He finally got it, in part because of a new focus on tree ring research.
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  Dendrochronologists such as Brian Black have benefited in
• 5:06
  recent years because more
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  SPEAKER_00: raw data has come from low elevation trees.
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  SPEAKER_00: Historically,
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  Most tree ring studies focused on high elevation trees because
• 5:16
  they are better at
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  SPEAKER_00: recording subtle climate change,
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  SPEAKER_00: often the issue that drives research.
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  SPEAKER_00: Low elevation trees are more complacent with less variable rings.
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  SPEAKER_00: They just grow no matter what, says Brian.
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  SPEAKER_00: The abundant growth has facilitated Brian's work on geologic hazards.
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  The better dating we have allows us not only to figure out the
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  relationship of
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  SPEAKER_00: geologic events,
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  SPEAKER_00: but also to exclude potential triggers,
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  SPEAKER_00: he says.
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  SPEAKER_00: In addition to the trees Pat found in 1993,
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  SPEAKER_00: Brian worked with trees collected at nearby Lake Kapowson,
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  SPEAKER_00: known by some as Stump Lake.
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  One of the coolest things I learned from the report is that
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  Kapowson is just
• 6:01
  SPEAKER_00: 518 years old,
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  SPEAKER_00: mostly in the region date from the end of the last ice age,
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  SPEAKER_00: circa 13,000 years ago.
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  Copaucin formed when the electron mudflow dammed two small
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  creeks and killed a
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  SPEAKER_00: forest,
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  SPEAKER_00: leaving upright trees later cut by loggers.
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  In 2015,
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  scuba divers pulled up cores from two submerged Douglas fir
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  trees,
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  SPEAKER_00: Pat told me,
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  SPEAKER_00: though,
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  that based on more than 40 years of sampling submerged trees in
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  the Cascades,
• 6:33
  western red cedars and whitebark pines are the only tree that
• 6:36
  lasts for more than a
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  SPEAKER_00: couple centuries after they die.
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  SPEAKER_00: With the additional trees and Pat's original trees,
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  Brian did what he had done previously on his and Pat's study of
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  the Seattle Fault.
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  He compared them with a master chronological data set of living
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  trees from Vancouver Island,
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  SPEAKER_00: that spanned the years 715 to 1990.
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  SPEAKER_00: The trees told of dying in the summer of 1507.
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  SPEAKER_00: This was a key discovery, Jim Vallance told me.
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  SPEAKER_00: Now that they knew that the lahar took place in the summer,
• 7:13
  Jim realized that snow and ice melt could have saturated rocks
• 7:17
  in the Sunset
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  SPEAKER_00: Amphitheater on the mountain's summit.
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  Previous work had determined that this was the source of the
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  debris and made a
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  SPEAKER_00: slope failure more likely.
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  Jim also told me that the dating eliminated potential collapse
• 7:31
  generators such as a
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  SPEAKER_00: heavy winter snowpack and an atmospheric river event,
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  SPEAKER_00: since those are usually restricted to the late fall or early summer.
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  SPEAKER_00: The new information didn't clarify what exactly triggered the eruption,
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  SPEAKER_00: but it could help disaster planners.
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  SPEAKER_00: If they know that an eruption is imminent in the summer,
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  the new data helps them be more prepared because they know that
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  rock high on the
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  mountain might be more saturated with water and thus more
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  susceptible to massive
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  SPEAKER_00: collapse,
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  SPEAKER_00: says Jim.
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  SPEAKER_00: Tying into the cultural lens history of place
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  SPEAKER_00: and people who have lived here for thousands of years,
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  SPEAKER_00: the paper mentions two indigenous stories that reference the electron.
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  SPEAKER_00: The young man's ascent of Mount Rainier,
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  SPEAKER_00: which comes from Arthur Ballard's mythology of southern Puget Sound,
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  SPEAKER_00: and the lake on Mount Rainier,
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  SPEAKER_00: which comes from Ella E.
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  SPEAKER_00: Clark's Indian Legends of the Pacific Northwest.
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  Both describe flood water and debris that buried the Puyallup
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  River Valley near the
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  SPEAKER_00: present town of Orting.
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  SPEAKER_00: As one member of the Puyallup tribe told me,
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  he has long used these stories as a way to illustrate the
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  enduring legacy of oral
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  histories and how they often provide details later teased out
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  by more recent
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  SPEAKER_00: science.
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  One aspect of the legacy of Lahars is that they devastate what
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  and wherever they encounter.
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  Loss of life,
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  loss of habitat,
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  destruction of communities,
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  destruction of travel routes.
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  SPEAKER_00: They are not to be trifled with.
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  SPEAKER_00: The great electron mud flow will not be the last to cause problems,
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  SPEAKER_00: and the more we know through good scientific research,
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  SPEAKER_00: the better.
• 9:13
  SPEAKER_00: The tree ring work is not only totally cool,
• 9:17
  SPEAKER_00: but also a key way to further relationships between people and place,
• 9:21
  SPEAKER_00: and hopefully help create more resiliency for future catastrophic events.
• 9:27
  Once again,
• 9:27
  this is David B.
• 9:28
  Williams,
• 9:29
  author and voice of The Street Smart Naturalist.
• 9:32
  SPEAKER_00: Explorations of the Urban Kind,
• 9:35
  a weekly newsletter and podcast focusing on the human and
• 9:37
  natural world around
• 9:38
  SPEAKER_00: Seattle,
• 9:39
  SPEAKER_00: Puget Sound,
• 9:40
  SPEAKER_00: and the Pacific Northwest.
• 9:42
  SPEAKER_00: If you'd like more details about my books,
• 9:43
  SPEAKER_00: walks,
• 9:44
  SPEAKER_00: and talks,
• 9:45
  SPEAKER_00: and a link to sign up for my newsletter and podcast,
• 9:47
  SPEAKER_00: check out my website,
• 9:49
  SPEAKER_00: geologywriter.com.
• 9:51
  And don't forget to slow down,
• 9:53
  pay attention,
• 9:54
  and enjoy the world around you.