Stop! There’s a tree in the rock in the road

But is it wild or urban?

The plant featured in this Street Plants post was a tough call. Is it urban or is it wild? It must be wild as it grows on the crest of the Laramie Range at 8500 feet elevation, enduring winds to 75+ mph and temperatures to -30º F (not counting wind chill). It got its start long before Euro-Americans arrived in southeast Wyoming. Yet it’s very much an urban plant, for it grows in the middle of Interstate Highway 80, one of the main arteries of America.

I-80 between Laramie and Cheyenne, Wyoming. Thin white bars on highway are trucks. Google Earth view.

Back in the spring of 1868, a Union Pacific rail gang laid track past a small limber pine growing out of some granite rocks. They were in a hurry but took time to divert the tracks slightly to avoid the tree. Then they rushed on, laying one mile of track per day! They were bound for Promontory Point, Utah, where the Golden Spike was driven on May 10, 1869, completing the United States’ first transcontinental railroad.

The small “struggling” pine by the tracks took on several names: Tree-in-the-Rock, Tree Rock, and Lone Tree. For 35 years, engineers would stop their trains to “give the tree a drink” in the form of buckets of water. But this tender loving care was not to last.

About ten miles to the west was a terrifyingly steep descent off the Laramie Mountains (and a tough climb going the other direction). In 1901-02, the railroad was moved to easier terrain a short distance south. The abandoned grade became a wagon road, and in 1913 it was designated part of the Lincoln Highway—our first transcontinental highway for automobiles:

“The Lincoln Highway was created to free automobile travelers from the confines of their urban environments, providing them a way, and a reason, to venture out toward distant horizons.” (source).

Distant horizons are common in Wyoming, so leave the confines of your urban environment and venture here!

The Lincoln Highway in 1916.  Added arrow points to the Tree-in-the-Rock's approximate location.

The Lincoln Highway honored the great Abraham Lincoln, our 16th President, most famous for the emancipation of slaves. About nine miles west of the Tree-in-the-Rock, he looks down on Interstate 80 at the Summit Rest Area.

Post card of “Tree-in-the-Rock, The Famed Landmark of Wyoming” (ca 1927 based on similar dated photo). From Wyoming Tales, no source given.

In the late 1920s, the Lincoln Highway became US 30. It was upgraded to Interstate Highway 80 in the 1960s. But the Tree-in-the-Rock survived. It had become so beloved that highway construction crews were forced to accommodate it. East- and west-bound lanes pass on either side, and there’s a small park for those with time to stop.

As I mentioned, Interstate 80 (New Jersey to California) is a major artery. In southeast Wyoming, it's dominated by trucks carrying goods to those in need. These are the red blood cells of America.

Sometimes the artery gets clogged; from WYDOT webcam near Laramie.

When I visited the tree last week, I struck up a conversation with a truck-driver, starting with what I was sure would be a good ice-breaker: “Would you like to see the tree in 1927?” I asked, showing him the old post card. It worked.

We chatted about the tree, railroads, trucking, how scary I-80 is in winter, and whether those were mountains (his opinion) or rocks (mine) on the horizon. He lives on Chicago’s South Side, and was east-bound from Salt Lake City, Utah, to Des Moines, Iowa, and then back to Chicago. He covers 2400 to 2900 miles per week! Do we ever think about the folks that drive the trucks that bring us what we need, or more often want? I do—on cold snowy days when the roads are closed, or even worse, still open but with traffic at a crawl. What an awful but important job!

A different view of I-80 near Lone Tree (WYDOT webcam).

This driver stops to learn something of the country he passes through. “If you don’t stop, you never will,” he advises—words as pithy as any Yogi-ism.

Truck driver in center of photo; his rig is the red one.

The photo above was the best I could do at replicating the old photo (note matching rock ridges on the skyline). Any further away and I would have been on the highway. The limber pine has a healthier canopy now. Maybe travelers still stop to "give it a drink."

Limber pine (Pinus flexilis) in late Proterozoic (1.4 billion years old) Sherman granite.

It’s producing cones, a good sign.

Limber pine cone on grüs—disintegrated Sherman granite.

The coarse-grained Sherman granite, with Abe Lincoln for scale.

Lincoln Highway marker on left. Are those rocks or mountains on the horizon?

The tree-in-the-rock-in-the-road is on the “crest” of the Laramie Mountains. It’s an odd crest—a flat tilted plain with scattered towers, ridges, walls and rock piles, all made of giant granite blocks. It looks like a playroom for a giant's children, where no one has cleaned up and put the blocks away. These are the Sherman "Mountains"—geologists call them “tors.” I’ve written multiple posts about them as they’re fascinating and irresistibly photogenic.

This will be my contribution to the Street Plants gathering on October 21. Have you had a recent encounter with urban wild plants? Consider joining us (stay tuned).

Tree on Drugs

Though it's early October, this American pussy willow is not thinking fall.

As you may know, I'm following a tree.  I’m not alone—fifty-plus other people around the world do the same.  Early each month, we “gather” at a site kindly hosted by Lucy Corrander to report on our trees.  And like so many trees, my willow hasn’t changed much since our last gathering.  Is it waiting for a hard frost?

Some leaves are yellow, but no more than last month.

This pussy willow was the first wild plant I saw in bloom this year—back in cold snowy February!  Salix discolor is famous for that.  Will it be the last to lose its leaves?

Mid-February: what a surprise to find this tree in bloom!  I had to follow it.

Since there’s little to report, I decided to investigate one of the willow’s more curious traits—it’s a tree on drugs.  It may not be addicted, but it certainly benefits from them.  So do we! And we have for a long time.

• • •

Back when botanists were mainly physicians and pharmacologists, some were experts in plant signatures:  shapes of leaves, sizes of roots, patterns of flower petals.  These indicated specific curative powers.  God had made plants for man's use, and He revealed the uses to trained eyes.  For example, the leaves of hepatica (liverleaf) are three-lobed like the human liver, and therefore cure ailments of the liver.  The eye-like flowers of eyebright (Euphrasia) point to treatment of eye problems.

Liver problems?  Try Hepatica transsilvanica (source).

This Doctrine of Signatures was in use in ancient Greece by the first century AD.  In the 1500s, the Swiss-German botanist-pharmacologist Paracelsus advanced and formalized it: "Nature marks each growth,” he wrote, “according to its curative benefit.”  Later the Doctrine expanded beyond shapes to include plant environments.  Diseases of a given habitat could be cured by plants of that habitat.  The biggest success was the treatment of agues—afflictions of damp lowlands (probably malarial fevers).

In 1763, the Rev. Mr. Edward Stone wrote a letter to the Royal Society describing in a scientific manner (for the day) the effectiveness of willow bark in curing agues, so “the world may reap the benefits accruing from it.”  He explained what had led him to try it:

“As this tree delights in a moist or wet soil, where agues chiefly abound, the general maxim that many natural maladies carry their cures along with them or that their remedies lie not far from their causes was so very apposite to this particular case that I could not help applying it.”

Stone gathered nearly a pound of willow bark, dried it for three months, and pounded it into a powder.  He soon had an opportunity to try it on a sufferer.  Not knowing effects nor potency, he first administered small amounts.  He observed some improvement, with not the “least ill consequences.”  With increased dosage “the ague was soon removed.”  Stone continued treatments for five years before he wrote his letter:

“It hath been given I believe to fifty persons, and never failed in the cure, except in a few autumnal and quartan agues, with which the patients had been long and severely afflicted; these it reduced in a great degree” (Stone 1763).

Stone collected bark of the “common white Willow”—Salix alba (source).

Thomas MacLagan is credited with the first clinical trials of willow bark, in 1876.  His interest was rheumatism.  First, he himself took salicylic acid and salicin (a derivative) with no ill effects.  He then gave patients suffering from acute rheumatism two grams of either salicylic acid or salicin, and found them equally effective:

“I have used salicylic acid and salicin in every case of acute rheumatism which has come under my care since November 1874 (a year and a half), and invariably with the same result—a rapid cure of the disease.  Seeing a patient suffering from acute rheumatism, I have no hesitation in assuring him that within forty-eight hours, possibly within twenty-four, he will be free of pain.”

Even though his training and approach were scientific, MacLagan still relied on the Doctrine of Signatures:

“It seemed to me that a remedy for that disease [rheumatism] would most hopefully be looked for among those plants and trees whose favourite habitat presented conditions analogous to those under which the rheumatic miasma seemed most to prevail. A low-lying damp locality, with a cold rather than warm climate, gives the conditions under which rheumatic fever is most readily produced” (MacLagan 1876).

As medicine progressed, the Doctrine of Signatures fell out of favor (it reappeared in the 1960s as “like cures like”—homeopathy).  But the efficacy of willow bark remained widely recognized.  Salicylic acid, which occurs in other plants besides willow, was first isolated in 1859, and was in factory production by 1874.

Salicylic acid has harmful side effects, mainly nausea and irritation of the stomach (salicin less so).  A German company, Bayer, found a way to convert it to acetylsalicylic acid, which is much more tolerable and equally effective.  They called it “aspirin”—combining “a” from acetyl with “spi” from spirea (meadowsweet), their source of salicylic acid.  In 1887, aspirin became the first synthetic drug, and remains the most commercially successful.  [Bayer lost ownership of the name “aspirin” at the end of World War I, a long story—see Jack 1997.]

But why do willows make salicylic acid?  What do they use it for? (probably not rheumatism)

Tree-on-drugs selfie.

Salicylic acid is a secondary metabolite, meaning it’s manufactured by plants (a metabolite) but is not essential (secondary).  Primary metabolites are used in fundamental pathways, and are found across the plant kingdom, whereas secondary metabolites are restricted to certain groups.  Their functions are diverse:  regulate growth, attract pollinators, deter predators, and more (see this excellent summary).  Interestingly, though plants make secondary metabolites for their own use, we humans find many of them valuable—quinine, digitalis, caffeine, nicotine, cocaine, and of course salicylic acid. [Hot-off-the-press:  A secondary metabolite, artemisinin, is the reason Tu Youyou is one of this year's recipients of the Nobel Prize in Medicine.  It's used in treating malaria.]

We may classify salicylic acid as secondary, but for the willow, it's hardly non-essential.  It plays important roles in “growth and development, photosynthesis, transpiration, ion uptake and transport. [It] also induces specific changes in leaf anatomy and chloroplast structure, [and] is involved in plant defense against pathogens” (source).

Humans are not the only critters that benefit from the willow’s drugs.  Some Chrysomela beetles eat willow leaves and sequester salicylic acid … not for rheumatism or headaches, but rather to make themselves distasteful to their predators.  Life will evolve to meet an opportunity!  For more, see To Make a Willow Weep at Catalogue of Organisms.

Join us!

Sources (in addition to links in post)

Jack, DB.  1997.  One hundred years of aspirin.  The Lancet 350:437-39.

doi:10.1016/S0140-6736(97)07087-6

MacLagan, T.  1876.  The treatment of rheumatism by salicin and salicylic acid.  Br Med J 1:627.  PDF 

Reader’s Digest.  1986.  Magic and medicine of plants.

Stone, E.  1763. An account of the success of the bark of the willow in the cure of agues.  Phil Trans 53:195-200.  PDF

Living Botanical History

Mrs. Aven Nelson holds a “stout carpenter’s chisel” used to dig up plants in Yellowstone Park.  Student assistant Leslie Goodding looks on.  Between them are felt “blotters” for drying pressed plants.

Last week I was invited to do living history, also called historical reenactment.  Fortunately, I accepted.  I say “fortunately” because … it was so much fun!  It was like being kids again—when we could “be” cowboys, detectives, astronauts, explorers or whatever we wished!  In this case, we were botanical explorers freshly returned from Yellowstone Park in 1899.

The occasion was an open house at the Rocky Mountain Herbarium, University of Wyoming—celebrating 122 years of service to the botanical community, and the exciting prospects of expansion (at a time when we bemoan the closing of collections).  Through demonstrations and exhibits, guests learned about plant collecting, specimen preparation, the value of herbaria, and the importance of our own herbarium.  At a million specimens, it's the ninth largest in the US, and is the largest collection of Rocky Mountain plants.

Student intern mounts a pressed dried specimen on herbarium paper with white glue.

Open house photos by B. Heidel, Wyoming Natural Diversity Database.

Botany Professor Greg Brown and Herbarium Manager Ernie Nelson describe a bright future for the Rocky Mountain Herbarium.  Behind them Aven Nelson is listening, surely a happy man.

The Rocky Mountain Herbarium began as the vision of one man—Aven Nelson.  Ironically, he was hired to teach English at the brand new University of Wyoming in 1887.  There were only six faculty, yet somehow the Board of Trustees mistakenly hired two English professors.  So Nelson’s career veered unexpectedly into biology, and then botany.  It was long and illustrious, ending with his death in 1952 (age 93).

In 1899, Nelson obtained permission from the US Army to collect plants in Yellowstone National Park.  He, his family and two student assistants traveled by horse-draw wagon and camped out for 14 weeks, returning home with 30,000 specimens! (they recently wrote of their adventures in Botanists in Paradise).  Most were duplicates, which were compiled into sets for exchange with herbaria around the world.  Other sets were sold to herbaria and private collectors to raise money for field work.  The Yellowstone project established the herbarium as a reputable and important institution, and the Board of Trustees of the University designated it the "Rocky Mountain Herbarium" that fall.

At the open house, I had the privilege of being Mrs. Nelson.  It was a special treat as I’ve been visiting with Aven and Allie Nelson’s grandson (97!), who grew up in his grandparents' home, and as a kid helped granddad with botany projects.  It was great fun to tell Tom I would be his grandmother for a day.  Ali, a history student, played 19-year old Leslie Goodding, one of the two student assistants in Yellowstone.

Mrs. Nelson reviews a field book; Leslie Goodding shows his “catch” for the day—a vasculum full of plants ready to be pressed.

Leslie Goodding replacing blotters, near the end of the expedition.  AHC.

The open house was a success—the herbarium was full of visitors.  Mrs. Nelson and young Mr. Goodding had a steady audience for over an hour!  They somehow managed to come up with a computer and slideshow of the photos that Professor Nelson took during the expedition—a convenient if puzzling convergence of the present and the past.

[If you’re on a mobile device and can’t view the show, many of the old photos are here.]