Super easy tree id ... while passing through Hell

Last winter, I wrote a post about using dichotomous keys to identify trees in the Rocky Mountains.  A dichotomous key presents the user with a series of choices, each with two alternatives.  At each step, a subset of candidate species is eliminated.  Eventually, the user arrives at a single species -- the tree at hand!

If we were to take this specimen though the key in the Rocky Mountain Tree Finder, we would decide first that it’s a conifer (without “regular leaves”), then a pine (with clustered needles, five or fewer per cluster).  Then we would choose five needles to a cluster, followed by needle-length of 1.5 inches or less ... voilà!  This is a bristlecone pine.

But there is an easier way to identify this tree, as I realized when it almost knocked me over while I was hiking the Cascade Falls trail east of Cedar City, Utah (map at end of post).  Just answer a single question:  “What kind of bottlebrush would it make?”

Left:  a branch of limber pine, Pinus flexilis, might make a usable bottlebrush in a pinch.

Below:  ponderosa pine, Pinus ponderosa, with its longer needles (4-9 inches), could be handy for cleaning jars.

This bonzai ponderosa pine is less than four feet “tall” -- hardly ponderous, but quite beautifully-formed in response to the harsh badlands environment.

I guess common juniper, Juniperus communis, might work if nothing else were available.

However, if there were a bristlecone pine tree nearby, you would toss your limber pine, ponderosa pine or juniper branches, for bristlecone branches look to be perfect bottlebrushes.

Botanists think bristlecone branches resemble foxtails, and in fact, three closely-related species are grouped into subsection Balfourianae, the Foxtail pines.  These include the Rocky Mountain bristlecone (P. aristata), the foxtail pine of the eastern Sierra Nevada in California (Pinus balfouriana) and the Great Basin bristlecone (P. longaeva) -- which is the one that I found along the Cascade Falls trail.  (The famous ancient bristlecones of the White Mountains in eastern California are Great Basin bristlecones as well.)

I didn’t expect to see bristlecone pines here, at only 8900 feet elevation, but the branches were a dead give-away -- lovely green bottlebrushes!

A bristlecone pine with the graceful symmetry of youth.

With the death of a main stem, this small tree already has developed the pitchfork growth form characteristic of aging bristlecones.

Bristlecone pines are named for the recurved bristles on the tips of the cone scales.

The Cascade Falls trail is located east of Cedar City, Utah, on Dixie National Forest in the vicinity of Navajo Lake.  Take the Navajo Lake turnoff south from Utah Highway 14.  Go about 0.3 mi on this gravel road, then turn left at the sign to Cascade Falls (small sign, only visible going west).  Follow this dirt road down to a gravel road in a drainage bottom.  Turn right (southwest) and continue to the road’s end and the trailhead.  Map from Google Earth.

There is much to see along the short trail to Cascade Falls, which passes through hellish badlands before arriving at a fount of clear, cold, gushing water emerging from a rock crevice!

Passing through hellish badlands ...

... to arrive at a blessed fountain,

... with smokey views of a distant Zion (National Park) en route.

but there s life in the old dame yet

There is an awesome beauty in old age, in the broken and twisted forms that record a long tough time on earth, and in the life that goes on in spite of it all.

Great Basin bristlecone pine, Pinus longaeva; White Mountains, California.  

This tree started its life around four thousand years ago, when fortuitous circumstances allowed a tiny seed to germinate and become established amid calcareous rock fragments, little moisture, and scant nutrient-poor soil.

Young bristlecones on harsh sites grow slowly, adding an inch or less of girth each century.  After five hundred years, the tree would have been in the prime of life, like the one to the left, sporting abundant green branches and fertile cones, and growing with the graceful symmetry of youth.

But of course youth doesn't last.  Over the next several thousand years, the trials of life left their mark.  The top of the tree was broken off, and a side branch took over.  Then the replacement crown itself was lost and replaced, creating a wooden pitchfork. Youthful symmetry was gone.

Great Basin bristlecone pines, with distinctive pitchfork growth forms.

Roots were exposed and killed by erosion, forcing parts of the tree to give up the ghost -- no more bark, no more needles, no more cones.  Eventually there were only a couple of narrow winding strips of bark left to carry nutrients and water from the soil skyward, and to transport photosynthesized sugars from the remaining needles.  By the time Edmund Schulman arrived in the White Mountains sixty years ago, this tree was pretty much as it is today -- mostly dead.

This bristlecone is down to two strips of bark, one on each side of the tree.
Edmund Schulman called them "life lines".

It was Schulman who discovered the longevity of bristlecones in the White Mountains.  In 1958, he reported there were 17 over the age of 4000, and the eldest, the Methuselah, was dated at 4600 years.  This set off a flurry of research that continues today.  The long-lived bristlecones have provided records of times and climates past, and insight into tree growth, reproduction and adaption to harsh environments.  Perhaps the biggest attraction is their promise of the Secret of Long Life, for even though these trees are ancient, they still enjoy the vigor of youth.

there s a dance in the old dame yet

toujours gai toujours gai

Like Mehitabel the old alley cat, down to just a single life, the ancient bristlecones still live it up.  If you follow a winding narrow bark strip skyward to the remaining green branches, you will find not only needles but cones as well -- healthy cones with abundant pollen and viable seed, produced at rates suggestive of the heady days of youth.  Yes, there’s life in the old dame yet!

Cone of a bristlecone, 3" long; note the eponymous bristles.

Even more impressive -- the oldest trees are the stunted ones on the harshest sites, growing just enough each year to keep a slender strip of bark or two alive, and to produce seed, which with luck the wind will carry to some equally inhospitable site.

Great Basin bristlecone seems able to thrive on very little.

What's the bristlecone’s secret to a long life?  The harsh environment in which it lives is part of the answer.  A bristlecone pine can grow quite well on more hospitable sites, but would be out-competed by other plants.  There is little competition on dry rocky nutrient-poor soils at 10,000 feet elevation.  The cold dry climate provides other benefits.  Microbial growth is slow, and agents of rot and decay that plague trees elsewhere pose few threats to most bristlecones.  Because plants are scarce and grow slowly, there is little litter on the ground to carry fire between the widely-spaced trees.

But there must be something about the bristlecones themselves that allows them to survive for many centuries where few other plants can grow.  They have quite a few tricks up their sleeve, actually.  Here are some of them.

Bristlecone needles stay on the tree 30 to 40 years!  New ones are added each growing season, but if there’s a particularly bad year when needle growth isn’t possible, older ones supply carbohydrates 'til things get better.

Bristlecone wood is dense and resinous, and highly resistant to rot, especially in a cold dry climate.  But it is not entirely immune.  The wonderful colors of dead wood are due in part to invading wood fungi, and chemical interaction between fungi and resin.

Even a fallen tree takes a very long time to decay.  In the meantime, the wood is sculpted and polished by wind, water and ice.

A bristlecone pine is composed of sectors.  If the roots of a sector are destroyed, only the tissue of that sector dies.  The rest of the tree lives on.




Left: sectored architecture and dieback.






Finally, bristlecones don’t senesce.  The small portion of an ancient tree that is still alive continues to grow with youthful vigor, producing healthy bark, needles and cones.  Even its DNA shows no sign of deterioration.  The seeds are viable, with no increase in mutation rate.  Shortening of chromosomes, seen with aging in so many organisms, doesn’t happen in bristlecones.  Can we really call these trees "old"?

This ancient tree may be mostly dead, but what remains is still young!

there s a dance or two

before i m through
you get me pet
there s a dance or two
in the old dame yet

Notes and Information Sources

toujours gai -- Fr.; always gay, happy, light-hearted

mehitabel the alley cat and her cockroach friend archy were reincarnated by don marquis in 1916, illustrations by george herriman

Discovery of the ancient bristlecones:

Schulman, Edmund.  1958.  Bristlecone pine, oldest known living thing.  National Geographic 113:354-372.

I am grateful to Ronald Lanner for sharing the details of bristlecone life, and for wonderful reading during my evenings in the White Mountains.  His Bristlecone Book is highly-recommended:

Lanner, Ronald M.  2007.  The bristlecone book; a natural history of the world’s oldest trees.  Missoula, MT:  Mountain Press Publishing Co.

The Ancient Bristlecone Pine Forest, in the White Mountains of California, is managed by Inyo National Forest and the Eastern Sierra Interpretive Association.

I wrote about the Great Basin bristlecone and other members of the Foxtail Pine group in an earlier post, Ancient Plants on Ancient Rocks.

Ancient Plants on Ancient Rocks

Several days ago I posted a short quiz featuring a mystery plant and a mystery rock.   Congratulations to Lockwood for highest score.  He named the bristlecone pine as well as the subsection of pines, the Balfourianae.  This is a really interesting group that I learned of just recently -- very cool, so extra credit Lockwood!  He also got the location (White Mountains of California).  Second place goes to Ronn, who identified the Great Basin bristlecone (Pinus longaeva) growing on dolomite, but had the unfair advantage of knowing the location and purpose of my expedition :)

The Plants

The Great Basin bristlecone pine, Pinus longaeva, is one of three species in subsection Balfourianae, the Foxtail Pines.  The others are the Rocky Mountain bristlecone pine, P. aristata, and the foxtail pine, P. balfouriana.  All three grow at high elevations in harsh conditions, and are extremely long-lived.  The Great Basin bristlecones are the most ancient -- "Methuselah" is thought to be the eldest, at least 4600 years of age.  Many of the stunted bristlecones in the photo below are 3000-4000 years old.

In spite of the habitat similarities of the three species, their ranges do not overlap.  Maps below are modified from Tree Species Range Maps (USGS); accessed May 2012.  This website includes both P. longaeva and P. aristata in the distribution map for the latter (corrected below).  At one time they were considered a single species, but Bailey (1970) provided convincing evidence for recognition of two species.  Current distribution information is from Lanner 2007.

The two disjunct clusters of foxtail pine shown above are recognized as separate subspecies:  ssp. balfouriana in the Klamath Mountains (including a population in extreme southern Oregon not shown), and ssp. austrina in the Sierra Nevada to the south.

The Rocks

In the White Mountains of eastern California and western Nevada, bristlecone pines grow on thin, nutrient-poor soils that develop from the Reed dolomite.

The Reed is massive, white to buff, fine- to coarse-grained dolomite (dolostone) that “weathers to form white, angular to spheroidal, resistant outcrops riven by joints of various attitudes” (Ernst et al. 2003).  It often is assigned to the Precambrian-Cambrian transition ca 600 to 520 million years ago.  Corsetti and Hagadorn (2003) consider it to be late Precambrian based on more precise dating of the PC-C boundary.

Why is it that such ancient trees are found in such extreme environments?  Even more impressive, the oldest bristlecones grow on the harshest sites!  This intriguing situation has puzzled people since the antiquity of the trees was first discovered, and has been the stimulus for a lot of research.  We now know quite a bit about bristlecone pines, though not enough to explain away all the mystery.  You can read more of their strange story at but there s life in the old dame yet.

Literature Cited

Bailey, DK.  1970.  Phytogeography and taxonomy of Pinus subsection Balfourianae.  Annals of the Missouri Botanical Garden 57:210-249.

Corsetti, FA.  2003.  The Precambrian-Cambrian transition in the southern Great Basin, USA.  The Sedimentary Record 1:4-8.

Ernst, WG et al.  2003.  Relationships among vegetation, climatic zonation, soil, and bedrock in the central White-Inyo Range, eastern California.  GSA Bull. 115:1583–1597.

Lanner, RM.  2007.  The Bristlecone Book.  Missoula MT:  Mountain Press Publ. Co.