Time perhaps for some geography. The Owens Valley runs north and south through a veritable alleyway between the enormous scarp of the High Sierra to the west and the more rounded and somewhat less daunting but still enormous and imposing White Mountain range to the east. White Mountain itself is the third highest in California and just a tad lower than Mt Whitney. These two ranges are practically right across the street from one another - US Highway 373 being that street - but ecologically they are different animals altogether. For (once again), the great Sierra scarp scrapes the Pacific rain clouds almost completely dry, leaving the Owens Valley in high desert, and the White Mountains are the westernmost range of the Basin and Range, a province of alternating mountain ranges and desert basins extending all the way to Salt Lake City. One high desert after another, broken up by narrow mountain ranges, looking on a topo map to be rippled like a pair of corduroy pants.
These Basin and Range mountains have a life pattern inverse to the more familiar pattern of ranges such as the Sierras and the Cascades, where generally the valleys and lower slopes have the richest vegetation while life on the peaks becomes increasingly spare. In the Basin and Range, the desert floor and lower slopes are generally too hot and dry for tree growth while at higher elevations, cooler temperatures and increased moisture allow forests to grow. The term for these is Sky Islands. First the juniper and pinon pine forests and then into white pines and finally, on the highest elevations across the Great Basin of Nevada and Utah, the Great Basin Bristlecone Pines.
Most Bristlecone stands are found between 9,000 and 11,500 feet, where conditions are relatively cool and moist. Here in the White Mountains, where 9 feet of snow falls annually and summer temperatures rarely hit 70 F., scientists have found stands of Bristlecone Pines that boast a dozen or more trees over 4000 years old, including one named Methuselah, over 4700 years old and long identified as the oldest tree on earth (it was recently dethroned by another unnamed Bristlecone Pine). This is the Schulman Grove, named after the guy who first explored and dated them. And here at the parking lot of Schulman Grove I found the temporary Forest Service trailer alongside the burnt remains and big black hole of the recently torched Bristlecone Pine Visitor Center.
Talk at the trailer was mixed. The ranger and the staffer from the Eastern Sierra Interpretive Center were attempting to focus on the usual work of touting and explaining these incredible trees, but the subject of the fire and the trailhead vandalism was hard to avoid. I talked briefly with the ranger who told me that John Loup. the ranger who had spoken at the bookstore reading, had been the major force behind building the Visitors Center and had planned to retire but now would stick around to see it through all over again. This was not a simple federal project. Private fundraising was crucial to building the Visitors Center, and forest fees cover only the assistant's salary. I never knew private initiatives like this existed in the Forest Service.
I left this all behind for a while and set off on the Methuselah Trail, a four-mile loop through the area where Schulman found the largest concentration of ancient trees, including the namesake Methuselah tree, long believed to be the oldest of the bristlecones. The weather was beautiful, the temperature perfect. The forest is mostly a mix of Bristlecone and Limber Pine. In its youthful and mature phases - its first 1000 years or so - the Bristlecone is a rather indistinct - dare I say homely? - tree, not easily distinguished from the Limber Pine. After that, the Bristlecone Pine starts working out a more individual look, and continues doing so for 1000, 2000, 3000 more years, eventually developing bizarre and dramatic contortions that really make them look like the oldest trees on earth.
They’re not tall, 30-50 feet on average, and thus easy to take in as a whole. They also space themselves out, though two or three might clump up together and become nearly indistinguishable from one another visually. Gnarled is the first word that comes to mind, but the second, less obvious word, is regal. Swirly, sweeping trunks, carved by windblown ice and sand into beautiful textures and shapes. Photographers love them in snow, burnished and sharp in a deep blue sky. No snow for me here in September, and the midday sun was getting hazy. So I concentrated on the life forms.
The primary feature of the tree that allows them to live as long and look as bizarre as they do is called sectored architecture. This means that the roots, trunks, and branches are arranged in semi-independent sections that contain damage when it occurs so that the whole tree is not harmed. Individual roots can die off, first some then many and finally most, but remaining roots continue to feed healthy branches. Gradually through its lifetime a Bristlecone Pine becomes a remarkable intertwining of dead and live limbs. What looks like a snag in fact has a live stem and branches.
Not always easy to distinguish live from dead. Some have far more dead wood than live bark and some have only one thin strip of bark, barely visible without close scrutiny, running up the tree.Most of the older looking trees have dead crowns, so sheaths of bare golden spikes shoot up into the sky. Many of the branches are also dead. Otherwise, live branches sprout foliage where they will. The thin line of life in the remaining roots still sprout forth leaves and branches in unpredictable and asymmetrical patterns throughout the edifice. This foliage is often thick and lush, in a clump somewhere along the mid to upper middle of the trunk, creating designs like crazy hats and accessories.. The effect is a foppish flamboyance; when they say regal I think they mean Louis XIV. Or Darth Vader. Or who knows what else.
While the presence of life makes the whole thing so valuable, the dominant visual character is dead wood. Plenty of the trees are in fact dead, golden brown and beige in early decay, white and gray further on, and they can last another thousand years or so standing dead like that. A wild juxtaposition of life and death.
Bristlecone Pines take root in the rockiest soil I have ever seen support trees. They cling to rocks, extend over boulders; some seem to emerge from nothing but a pile of rocks. The soil is a light beige, glaring in the bright sun, and this, I learn, is no coincidence. It is dolomite, a mineral-poor soil that few plants can survive on, and in fact the Bristlecone forest has nearly no undergrowth. Dolomite’s light color reflects 25% of the sunlight and holds water well, making for soil that it is several degrees cooler than on the adjacent sandstone soil. The Bristlecone Pine takes advantage of this extra moisture while tolerating the soil’s low nutrients. A trail sign points to a steep slope across the valley where the juxtaposition of bristlecone habitat and sage habitat is stark, solely due to change in soil. Once soil changes, the landscape reverts visibly and abruptly to the prevailing brush.
The narrow trail cuts across steep rocky slopes only as evenly as it can, and more than once I almost went hurdling downslope, having momentarily forgotten the precariousness of my position as I maneuvered for a better angle on a particular tree. It would be a rough tumble. The steep slopes are a problem for the old trees as well. Erosion slowly washes away the ground around them, exposing their shallow roots. Many Bristlecone roots run above the ground's surface, sometimes with a sliver of life remaining, more often just dead burnished wood. It’s one of the ways they die, eventually toppling over, eventually remaining the operative word.
The hike was spectacular, and far more exhausting than most any other nature trail I‘ve ever taken. In three hours I had made it only the first two miles of the four-mile loop and I was shot. Not physically so much as mentally - aesthetically? - exhausting, like a three hour walk through the Museum of Modern Art, viewing the work of an endlessly inventive sculptor. I sat down in the shade of some exquisite mountain mahogany and read the trail guide, which was also pretty challenging. This is one well-researched tree.
The bristlecone pine was dragged from the obscurity of the high desert in the 1950s by Dr. Edmond Schulman of the University of Arizona Tree-Ring Research Laboratory. Schuman wasn't just out looking for old trees; he was studying tree-rings to detect climate change. He had discovered, or intuited, that trees growing in the most marginal of environments - at high elevations, on rocky soil and windy ledges - are more vulnerable to variations in climate, so their growth rings more precisely record such fluctuations. A dwarf tree with roots anchored in cracks and crevices has only that year’s precipitation to live on, so its growth patterns provide clearer historical records of the amount of moisture received than does a tree growing in well-watered bottomland that has access to a steady groundwater supply even in drier years.
Obviously the older the tree the longer the historical record its rings record. Schulman didn‘t expect to find anything as old as the 3000-year-old Giant Sequoias then presumed to be the oldest trees on earth, but his explorations surprised him. Not only did the gnarly looking trees out on rocky ledges have clearer growth ring records, they were often much older than trees of the same species that lived in better watered areas. The oldest ones turned out to be those living in the most difficult living conditions - a surprise. Higher and higher he went, testing gnarled and more gnarled trees, finding an 860-year-old Ponderosa, a 975-year-old pinon pine, a 1650-year-old limber pine.The remarkable and counterintuitive evidence indicated the oldest dwarves, eking out a living in the toughest of circumstances, tend to outlive the giants living large on flat moist ground.
In 1953, on a tip from a forest service ranger, Schulman investigated the Bristlecone Pine forest. He started up high, at a huge tree called “the Patriarch”, but found the Patriarch was a mere 1000-1500 years old. So he struck off to the outer edges of the forest, to the rocky soils, the southern exposures, the least promising environments, and sure enough, he soon found a 4000-year old tree. Over the next six years he found 17 bristlecone pines 4,000 years old or more in the White Mountains, nine of them along what is now known as the Methuselah Walk, after the tree he named Methuselah, which he dated at nearly 4700 years old, the oldest known tree in the world at the time, more than a millennium older than the oldest dated Giant Sequoia at the time.
(Subsequent study has determined that Methuselah turned 4500 in 2009, giving it a birthdate of 2491 BC! However, Methuselah is no longer champion. Tom Harlan, an Arizona research lab guy, finished analyzing a Great Basin bristlecone that is even older, over 4800 years old. He is keeping its location a secret.)
They can survive in an area nearly nothing else can. They live in a tough environment: high elevations, cold, dry, and windy. This helps reduce or eliminate many of their putative predators. Insects and beetles can’t stand these conditions. Too cold for the bark beetles that plague so much western pine stands. Fungi grows very slowly. Fire does not pose much of a threat to these outlying BP‘s. The soil is so harsh that little undergrowth exists. Fires from lightning might burn only the stricken tree, having no brush to feed on. The trees are spaced widely apart. Available oxygen at this elevation deters fires. BP’s can grow in better climates, and can grow faster and bigger. But they don’t live anywhere near as long in those places because they are susceptible to the hazards of bug, fungi, and fire that can also thrive better there.
Slow growth makes for tight tree rings and thus for harder wood. In dry years they shut down almost entirely. “Some of the old trees have been adding only an inch or less of rings per century throughout their long lives.” Scientists have found no evidence of senescence in the Bristlecone Pine. The essential functions of Great Basin bristlecone pine show no signs of deteriorating with age. Tests included reproductive capability. Methusela can still do it.
Schulman believed that while the Bristlecones were older than the Giant Sequoia, the latter retained the potential to attain the greater age. The oldest bristlecones, he felt, had only another 500 years at best, while the Giant Sequoias could live another 3000 years if spared disturbance like windfall and fire. I don’t know if this thinking stands today, but even the notion of having two distinct tree species so old we don't even know their potential lifespans is pretty awe-inspiring.
And that’s just the living tree. It lasts a long time, on a live tree, standing on a dead tree, and finally on the ground. Research found that Bristlecone Pine dead wood remained intact on White Mountain for another 5000 years, extending tree ring data back to 6700 B.C, greatly expanding the ability of tree-ring science - dendrology - to study climate in these trees. This lifespan not only dwarfs North American civilization, but challenges Western Civilization itself.
Schulman published the story in National Geographic in March 1958 and died of a heart attack the same year, at age 49.
Rested, I got up and basically power hiked the last two miles. My brain was filled and my senses so satiated I was no longer able to register the phenomena around me, phenomena that included the Methusela tree itself, unmarked for its own protection. I would have to come back another time to properly absorb this four-mile hike. Back at the trailer I shared with the Interpretive Woman my insight that the trail brochure should encourage hikers to carry lunch in order to have the strength to see it in one go. She didn’t seem to tune in. So we chatted again about the goings on. She told me the trailhead vandalism included cutting break lines, and that in her opinion the backcountry was too dangerous at this time. She would not go backpacking in this climate.
But I was in a place of dreams. I walked across the parking lot to my car thinking I had come a long way for a once in a lifetime opportunity and wasn’t going to be scared away. I was where I wanted to be and was going to go backpacking. In fact I was going to drive straight to Independence and begin another two-night backpack up to Kearsarge Pass. I sure hoped no one would smash my windshield, but if someone did I would have to be up to that challenge. I sure as hell wasn’t going away.
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