A Tale of Two Pullouts: Yosemite Valley From a Different Angle

El Capitan and the Merced River from the east

I know that I am truly privileged living as I do only a two-hour drive from one of the most sublime places on Earth, Yosemite Valley and the Sierra Nevada. We head up there two or three times a year, sometimes with students in tow, and sometimes on our own, so in 30+ years we've been there at least 100 times.

And I never get tired of it.

Part of the allure is seeing the seasonal changes. Winter provides the coating of snow, while fall provides the changing colors of foliage. Spring offers surging waterfalls and wild river flows. Summer provides...well...crowds, but also nice moments in places we learn of where the crowds can be avoided. We have favorite meadows and lakes for instance where people rarely stop. No matter when or where we visit, there always seems to be something new or different.

The Cathedral Spires are tucked away on the east side of the Cathedral Rocks at Bridalveil Falls

I know how it is if one gets to see Yosemite Valley for the first, and maybe only time. I've had that experience at so many other places around the world. The time available may be very limited, one may be part of a tightly controlled tour, and no one wants to miss any of the most famous views or hikes. And so it is that there is the required stop at Tunnel View, Bridalveil Falls, Cook's Meadow for the view of Yosemite Falls, and maybe Ahwahnee Meadow for a view of Half Dome. The walk to Lower Yosemite Falls, or Nevada Falls. And the Visitor Center. It makes for a full day, and a fulfilling day too. One of the most spectacular days you might ever experience.

And I never get tired of it. I'm perfectly happy to hit those same spots on my 101st trip to the valley. The season, the time of day, and the weather all conspire to make each stop a unique experience of wonder. But sometimes there are changes of a different nature, and that makes some trips really memorable. That is what today's collection of views is about.

Sentinel Rock rises above the south side of Yosemite Valley across from Yosemite Falls

Since the time that Yosemite Valley became a park, suppression of all forest fires has been the official policy. It was not however the natural condition of the parkland, nor was it the normal condition of the valley floor over the last few thousand years when it was managed by the original inhabitants of the region. 

The Ahwahnechee people, with roots among the Miwok and Paiute peoples of both sides of the Sierra, depended in large part on the acorns of the Black Oak and grazing animals like deer or bighorn in Yosemite Valley. It was in their best interest over the centuries to allow fires to burn through the valley floor and hold the quick-growing conifers at bay. When the park administrators put an end to the fires, the pine and cedar trees choked out meadows (only 65 acres of the original 750 acres of meadows remain) and grew into impenetrable thickets, blocking views of the canyon walls above.

What's worse is that choking off small fires can cause a buildup of fuel in the forest that could only lead to much worse fires than usual. This was always a danger, but it is far more hazardous today in a time of warming climate and extended droughts. Every Californian is fully aware of how wildfires in the state have morphed into monstrous events without parallel in written history.

The National Park Service has come around in their fire philosophy, especially after extensive fires a few decades ago in Yellowstone and Mesa Verde National Parks. They have instituted new policies of prescribed fires and selective tree removal to make the parks safer, but also to enhance the experiences of park visitors. In what way? The views.

The distinctive profile of the Three Brothers is the result of parallel jointing, or fractures in the granite that occur as the rocks are exposed by erosion

There are the parking lots that attract the majority of park visitors, but on the roads that loop around the valley there are many small pullouts, enough for perhaps three or four cars. In years past there seemed no real purpose for them, as they were surrounded by thick forest and offered no views or trailheads. On our visit a week ago, I found that two of those previously uninteresting pullouts had had the forest thinned out, and that they now possessed some outrageously spectacular views! The familiar iconic cliffs were there, but from angles I had never really seen before. In particular there was the long vertical cliff extending east from El Capitan, a view of the rarely seen Cathedral Spires (as opposed to the Cathedral Rocks at Bridalveil Falls), the vertical pillar of Sentinel Rock (often missed by people staring at Yosemite Falls), and the Three Brothers, which have never really had a designated viewpoint and are usually hidden by the tall trees. Upper Yosemite Fall was visible as well, perhaps farther away, but how many of you Yosemite veterans can recall seeing the falls with not a single other person in sight?

Yosemite Falls from a pullout west of Swinging Bridge

We had a leisurely lunch at the pullouts and wandered about taking pictures, and only two or three cars pulled off the road, and no one else actually got out. Except for the noise of passing traffic on a crowded Sunday afternoon, we literally had the best of Yosemite Valley to ourselves.

Prescribed fire in Yosemite Valley, with Half Dome and Clouds Rest in the distance.

We stayed at the park through Monday morning, and when we stopped by Tunnel View we witnessed another chapter in the new fire/forest regime: the ignition of a prescribed fire. It was done in March because the ground was still damp enough to prevent the uncontrolled spread of the fire. If you are on Facebook and would like to know more about forest management in Yosemite, check out (1) Yosemite Fire and Aviation | Facebook.

Yosemite Valley This Week: A Moment of Spring Richness and an Uncertain Future

 

I admit it. I fear what lies ahead. That's not the usual opening statement in a photo-essay of Yosemite Valley at its best moments. But that's the problem. I was there last week, when the heaviest snowmelt should have been weeks in the future. And the valley was at its best, a lovely escape from the summer-like heat of the Great Valley downstream.

But the peak runoff is not weeks in the future. It is probably already past. This year's snowpack was an unmitigated disaster. The few storms that did come dropped a bit of snow, enough in some years to get by, but very warm and dry conditions during April dropped the snowpack to around 5-10% of normal, or what passes for normal in these uncertain times. The snowpack would usually keep the famous waterfalls busy until mid-June or even July, but many of them may be dry within a few short weeks. And then the fires will come. I don't know what lies ahead for this most beautiful of valleys, but a disastrous fire has to be considered as a possibility.

The natural condition of the floor of Yosemite Valley has always been controlled by wildfire. Lightning strikes have caused fires for thousands of years, leaving the valley floor as a patchwork of open meadows with a few mature oaks and ponderosa capable of surviving the occasional grass fires. When humans first discovered the valley thousands of years ago, they continued the practice of burning the valley floor every few years. They had their motives of course; the acorns of the fire-resistant Black Oaks provided much of their diet, and the hunting of game was easier when the prey was in an open meadow rather than a deep forest.

When the valley was "saved" by turning it first into a state park in 1864 and later into a national park in 1890, fire suppression became the governing philosophy. The park's original 745 acres of meadows were invaded by young saplings and the 65 acres of meadows today represents only 7% or so of their original extent. It didn't help that drainage outlet of one of the wetland areas was dynamited to keep down the mosquito population.

Much of the valley floor has become a thicket of young and unhealthy conifer trees, a fire hazard of the highest order. The park service has come around to accept the need for fires in the management of the valley, but their success has been spotty and controversial. Prescribed fires have been done in some areas of the park, but more than one has gotten out of control and damaged structures. And prescribed fires are done when soil and fuel conditions are on the wet side. That is not the case at Yosemite this year.

An alternate practice was begun around a decade ago, and it too has been controversial. Instead of burning, the park service has been allowing tree-cutting to be done in some areas to remove the unhealthy trees. The buzz of chainsaws does not seem compatible with the general notion of "preserving" natural lands, but it may be a necessary evil. It led to an unexpected change for me as we visited the park last week.

Everyone always seems to be in a hurry as they scurry through the park looking for parking spots. The traffic was a problem because the free park shuttles weren't running due to the pandemic. So to see the many features of the valley, one had to park and hike quite some distance, or else drive from parking lot to parking lot looking for a good view. I was letting traffic pass by pulling into roadsides that normally don't offer much in the ways of views. But this time was different.

A lot of trees had been cleared from a pullout that I knew had never had much of a view before. No one else was there, but as I got out I could see something was different. The rocks above were, well, unexpected. I've struggled at times to get an interesting angle on the Cathedral Spires (above), but they were easily visible. And as I turned, I realized the Three Brothers were also in the open (below). 

And as I turned yet again, I had a full-on view of El Capitan that showed the full expanse of the cliff from the "Nose" to Horsetail Falls. The sawn-down trees in the foreground were perhaps a sad mess (that will be cured in time by natural forces of decay), but the view of the cliffs was dramatic and quite unexpected. We sat in the pull-out and enjoyed a quiet lunch.

The Pacific Dogwoods were in full bloom. The trees are a somewhat nondescript part of the understory for much of the year, but during the spring the flowers are dramatic (and for the biologists among you, I know that the big white petals are actually modified leaves or bracts, and that the true flowers are in the "button" in the middle). 

Our journey through the valley was our first in nearly a year. It included a stop at one of the most congested spots, but as is always true, there was a reason for its popularity. The Tunnel View is close to the spot where European colonizers first viewed the valley in 1851. The party, a militia trying to chase down a group of Ahwahnechee people, was largely unimpressed with the valley. But their medic, Lafayette Bunnell, was deeply moved by the sight, and later interviewed Chief Tenaya and others to learn what he could of the valley. He is credited with the names of many of the features, including the name of the valley itself. Yosemite seems to have been a derivative of the Miwok name for Grizzly Bear. Their actual name for the valley was "Ah-wah-nee".

So a hot and dry summer season looms. I hope for the best.

Looking Down on Yosemite: A Return to Taft Point

I don't know how it happened, but somehow 12 years slipped by since I last made the hike out to Taft Point above the floor of Yosemite Valley. It's not that tough of a hike, only 1.1 miles with just a bit of climbing on the way back. But what a payoff at the end. There is nothing quite like standing on the brink of the ultimate abyss.

The trail begins at a parking lot about two miles up the road from Glacier Point. Parking is limited and fills quickly, so be sure to arrive early in the day, or you'll be walking a lot farther from your parking spot. Or you can do what I did and wait until about the last day of the season before a major snowstorm, and come at the end of the day when the sun is quickly sinking below the horizon.

The beginning of the trail in the deep Red Fir forest gives few hints of the grandeur that lies beyond. It almost immediately passes an unusual outcrop of almost pure quartz (remember y'all, it's a national park; no collecting!). The trail plunges into the forest and crosses Sentinel Creek, which a short distance downstream falls over the brink of Sentinel Falls, more than 1,000 feet high.

The trail breaks into the open, and one can sense the edge of nothingness that lies beyond. And then there's a distraction! There are huge open cracks near the cliff edge that split the rock for hundreds of feet. These are called the Taft Fissures, and they are a bit of evidence for the geology that led to the formation Yosemite Valley itself. The fissures follow distinct cracks in the granitic rock that makes up the cliffs in this area.

One of the Taft Fissures. The "layers" are exfoliation fractures, a process related to jointing.

Granite forms miles below the surface as molten magma within the crust cools slowly, forming a coarsely crystalline rock. The rocks are under tremendous pressure from the overlying rock, but over time the rocks are uplifted and erosion strips away the "overburden". As the rocks approach the surface, they expand in volume, but being solid, they crack to form joints. On the scale of Yosemite Valley, the joints were points of weakness that could be exploited by flowing glaciers to carve and cut away at the cliffs. Many of the sheer cliffs of Yosemite are joint surfaces. Unfortunately, many rockfalls begin with joints that give way along the vertical cliffs.

At Taft Fissures, the joints allowed water and ice to get into the interior of the rocks, causing the minerals on the surface of the rock to crumble to quartz gravel and clay dust. As the cracks widened, boulders would occasionally fall in and become wedged inside, as seen in the picture above.

Just beyond the fissures, the world ends...the cliff edge is the beginning of a sheer 3,000 foot drop to the valley floor below. The perspective is both stunning and dizzying. It's hard to believe, but the viewpoint makes El Capitan look almost...small. It's scattered in with so many other steep cliffs.

The fast-setting sun illuminated the cliff of El Capitan and the scar of the September rockfall from the cliff at Horsetail Fall. The first view in the picture above is not actually Taft Point. The point is on the upper left. I would have to head up there to get the entire view.

There are four stunning viewpoints within a short walk of Glacier Point Road. Washburn Point, seen in the last post, emphasizes the wilderness lands upstream of Yosemite Valley (and a side view of Half Dome). Glacier Point provides a look straight down into the upper end of the valley, extending from Half Dome and Tenaya Creek Canyon to the area around Yosemite Falls. Sentinel Dome provides a 360 degree panorama of the entire region, but without the dizzying look straight down sheer cliffs. It is accessed from the same trailhead as Taft Point.

Taft Point picks up the view of the valley floor at Yosemite Falls and provides a panorama of the western parts of the Yosemite Valley, taking in the Three Brothers, El Capitan, and the Cathedral Rocks which soar above Bridalveil Falls (which are hidden on the far side). The sweeping view also takes in the western slope of the Sierra Nevada, leading down to the Mother Lode foothills and the Great Valley beyond.

Although the rockfall at Horsetail Falls in September has garnered all the news these last few weeks, the view from Taft Point takes in a perspective on the largest historic slide in the valley, which happened in 1987. An estimated 600,000 cubic meters of rock came down the cliff of Middle Brother (on the right side of the picture above). Luckily, no one was hurt as the Park Service had shut down the road when loud sounds of fracturing rock were reported coming from the cliffs above. The September rockfall, in contrast, was a bit over 10,000 cubic meters.

The cliff of El Capitan and the sheer cliffs of the Cathedral Rocks form a constriction in the western part of Yosemite Valley. Sometimes called the "Gateway", the rocks stand out because they are relatively unjointed, and thus were more resistant to the cutting and quarrying action of the glacial ice. The barrier even extends underground. Beneath the cliffs, the sediments are only about 300 feet deep. Farther up the valley, the sediments are around 2,000 feet deep. The glaciers at times had to flow up and over the sill of granite.

Taft Point is an amazing place. If you have a fear of heights, this will be a good place to either cure it forever, or amplify the condition to the point that you will be a whimpering mass of a nervous wreck. I don't mind looking over the edges of cliffs myself, although it will sometimes be on my belly. One never knows when one might have a fainting spell, after all. But I cannot watch others standing on cliff edges, especially if they are my students. I tell them to do their antics on their own time.

The sun hit the horizon and the sky exploded into flaming orange and pink. I quickly headed up the trail and back to the car so Mrs. Geotripper and I could have a nice dinner back down on the valley floor. It didn't matter that it was dark. The moon was up and we could still see the cliffs above, including a constellation of lights from at least fourteen climbing parties on El Capitan.

If These Cliffs Could Talk: Wa-ha'-ka, the Three Brothers Who Are All Out of Joint

Actually the Three Brothers are just full of joints, and that's the problem.

If any legends exist concerning the rocks known as the Three Brothers in Yosemite Valley, they have not come to me via the anthropologists or the internet. The rocks seem have been called Wa-ha'-ka, Wawhawke, or Kom-po-pai-zes, with meanings that include leaping frogs, couples enjoying each other (to use a family-friendly description), or the one that makes the most sense to geologists, "falling rocks". Rocks fall in Yosemite on a constant basis, but the Three Brothers are prizewinners in that regard.

The rather boring English name came from a historical event when James Savage's militia (the Mariposa Battalion) caught up to three of Chief Tenaya's sons near the base of the rock in 1851. It's a pretty mundane name, and I would really love to see a campaign started to officially re-name all of Yosemite's most prominent rocks with their ancestral First Nation monikers.

In any case, Wa-ha'-ka is a unique cliff for the three striking peaks, Eagle (the highest), Middle Brother, and Lower Brother. The triangular shape is derived from the joint pattern that courses through the cliffs. As mentioned previously in this short blog miniseries on Yosemite, joints are the fractures that occur in granitic rocks as they reach the surface and come under lateral pressure from nearby fault zones or regional stresses. There are two intersecting joint systems that formed the Three Brothers, one descending about a 60 degree angle. It can be seen best from across the valley at Taft Point, and the related Taft Fissures. The joints run through El Capitan granite and Sentinel granodiorite.

The Three Brothers and Yosemite Falls from Taft Point

Notice in the photo below how the slope in the foreground near Taft Point is angled the same direction as the joints at Three Brothers across the valley. There are many good reasons to make the short hike out to Taft Point, and this is one of them.

There is a very good reason thinking that First Nation name of the rock means "falling rocks". Crossing joints provide the instability that leads to slope failure. The rocks here fall often, and indeed in 1987, the largest recorded rockfall in recorded history at Yosemite took place at the base of Middle Brother. Thankfully the park road had been closed as a precaution and no one was hurt.

The Middle Brother Slide

The park historian at the time, Jim Snyder, was standing in the meadow below and described what happened (from Wieczorek et al., 1992*):

At 2:47 p.m. PST on March 10, 1987, a large rock fall dropped 800 m from the face of Middle Brother and spread rapidly across a talus cone, covered Northside Drive, and sent boulders across the Merced River. Much smaller rock falls from Middle Brother had begun on March 8, and by about 2:20 p.m. on March 10, because of an increasing number of rock falls and audible rock popping noises from the face of Middle Brother, Northside Drive, the main exit road from the valley, had been closed and the portion of Leidig Meadow below Middle Brother had been cordoned off.

...Jim Snyder observed the rock fall initiate as an intact planar slab of rock that separated from the cliff face. As the slab fell it appeared to shorten in a folding-like manner similar to the steps of an escalator. The slab disaggregated into a rock avalanche upon hitting and sliding along a prominent ledge before falling onto the talus cone below.

Another large rock fall from the face of Middle Brother occurred later that day at 5:10 p.m. The volume of these rock falls totaled an estimated 600,000 cubic meters of material weighing about 1.3 million metric tons. Dozens of smaller rock falls continued during the next several days..."

*Wieczorek, G.F., Snyder, J.B., Alger, C.S., and Isaacson, K.A., 1992, Rock Falls in Yosemite Valley, California, U.S. Geological Survey Open File Report 92-387, 186 pages.

High Water in Yosemite III

We continue our journey through Yosemite Valley during the peak runoff last week (part I here, and part II here), when the Merced River exceeded 7,000 cubic feet per second, and reached flood stage. Numerous meadows and trails were underwater, and it was a wonderful thing to see! Above is the view from in front of the chapel at Old Yosemite Village. The slope on the right is the lower part of the Three Brothers, with the Cathedral Rocks in the distance.

And above we have a flooded portion of the meadow at the base of El Capitan. Once again, we are looking at the incredible Cathedral Rocks with the Cathedral Spires on the left.

The gaging station that measures the discharge of the Merced River is just upstream of Pohono Bridge. The problem with bridges is that we tend to put them at the narrow parts of river channels. When the floods come, the bridges can cause a bottleneck effect, having all kinds of implications upstream and downstream. Some of the bridges have been redesigned in recent years to allow the river to flow in a more natural pattern and to stabilize bank erosion.

As noted in the previous posts, floods are not a particular problem for the natural ecosystems of the valley. The ecosystem developed under a seasonal pattern of flooding and drought. The floods can be a minor inconvenience to hikers on the valley floor, as in the picture above where the riverside trail is flooded.

Trees that grow too close to the river will have their roots inundated. If the flood lasts for any period of time, the trees will suffocate and die. Usually the high water backs off within a few days. Today, a week after my trip, the river is flowing at 3,160 cubic feet per second, half of what it was a week ago, but still about 50% above normal for the middle of June.

Update: Martha at Martha's Musings was in Yosemite at the same time. See some nice pictures here.

Staring into the Abyss #2 - Yosemite as you (maybe) have never seen it

Today, the view from the edge of the abyss (again from Taft Point) is to the north, towards Three Brothers and Yosemite Falls. Jointing plays a prominent role in the scenery of this view, both in the diagonal joints that form the western slope of the three spires of the Brothers, and in the horizontal joints that provide the two steps to the falls of Yosemite Creek. The rock on the right side of the Brothers is the Sentinel granodiorite, described earlier here, while the rocks on the left is the El Capitan granite, described here.

Jointing occurs as removal of the overlying rocks by erosion releases pressure, and the rock expands and fractures. It provides an avenue for water to enter the interior of the rock face and start the chemical weathering process, leading to the loosening of the boulders in the cliffs. The Three Brothers, with their intersecting joint sets, are a constant rockfall hazard. The white scars are recent slides and falls, including the 1987 Middle Brother slide, which with an estimated volume of 600,000 cubic yards, was the largest historic mass wasting event in the valley. Luckily, the National Park Service had closed the road below in anticipation, and no one was injured in the event. Other rock falls have produced injuries and deaths, including on the nearby trail to the top of Yosemite Falls.