Monday, November 26, 2018

Fall Finally Arrives, California Style

I would never try to compare our fall season with the hardwood forests of New England and the Appalachians, or even with the aspen groves of Colorado or Utah. But there are a few benefits to experiencing fall here in California.
For one thing, our fall lasts for a couple of months, and our trees are at the height of their color at a time when the trees back east are barren of leaves, and winter-style snows are lashing the landscape. It was 68 degrees out yesterday (though we had a day of light frost last week).
I walked the Tuolumne Parkway Trail this morning after a week on the road, and the changes were pretty obvious. The willows and wild grapes were changing.

There are also some mature cottonwood trees that have been various shades of yellow for weeks now.
But we also have some brilliant colors in the city as well. I had errands in town and took a few shots of the Modesto neighborhoods where Modesto Ash was planted many years ago.
There are other ornamental trees on our west campus that are relatively young, and they turned almost fluorescent over the holiday weekend.
So yes, I would never presume to say our fall show of color can compare to the wild displays back east, but I certainly enjoy having a few weeks to appreciate the changes that are happening here right now.
There is a lot of horror going on right now in so many places. I'll be back to trying to right the wrongs soon, but for a few moments today I took a few breaths of blessedly clean air (the Camp Fire is out, thank heavens) and enjoyed the technicolor show.

Monday, November 19, 2018

The Way It Was: The Deep Grassy Valley of the Ahwahnee

No geology exposition in today's post. Our state is choking in a toxic inversion layer filled with ash and particulate soot that is a sad reminder of the lives lost and lives destroyed by a horrific wildfire in the North State. Just for today, a reminder that beauty surrounds us in the depths of tragedy and suffering.
Half Dome reflected in the waters of the Merced River at Sentinel Bridge
Ahwahnee was the Native American name for Yosemite Valley. It's meaning is muddled in time, but it probably means the "Big Mouth", or the "Deep Grassy Valley". It was an island of clear skies and clean air above the smoke and ash. We only had a few hours to visit, so we headed to Sentinel Bridge for a short stroll, and as the sun set in the west we made for the Gateway View at the west end of the valley.
Sentinel Rock from Sentinel Bridge
Sentinel Rock is an astounding vertical cliff that rises nearly 3,000 feet above the valley floor. It receives somewhat less attention than some other rocks and cliffs in Yosemite Valley because it rises behind people who are staring in awe at Yosemite Falls on the north side of the valley.
Yosemite Point and the dry Yosemite Falls
Speaking of Yosemite Falls, there wasn't much to see of them. There was the barest trickle of water that did no more than wet part of the cliff. That should change this week as the first winter storm of year arrives (weeks late). We need it desperately, and many storms thereafter. When the falls aren't there, one's eyes are free to wander over the incredible cliffs that surround the dry watercourse. Yosemite Point and the Lost Arrow stood out boldly in the sun (in the picture above).
We barely had time to reach the Gateway View before the sun settled below the horizon. Only the vertical face of El Capitan was still catching the rays of light, and it soon faded.
The Moon peeked out from the cliffs to our right.
As the valley floor settled into darkness, the sky still glowed. It was a peaceful scene, filled with a serenity that is so sadly lacking right now. We enjoyed the scene until the darkness descended and we headed home.

To help those whose lives have been destroyed in the fire, you can find some ideas here:

Friday, November 16, 2018

A Journey of Ten Million Years...the Salmon of the Sierra Nevada

Chinook Salmon attempting to enter the fish ladder at Camanche Dam on the Mokelumne River
They've been coming here for at least ten million years. Every year, without fail. The lands changed, but still they came. If one waterway was blocked, they eventually found another. Sometimes they were isolated, and could never return to the sea, but they survived anyway. They are the salmon and trout of the Sierra Nevada.
Stanislaus River at Knight's Ferry

Anadromous fish are those that live much of their lives in the oceans, but which return to freshwater streams to reproduce. One might wonder why they would have such a complicated breeding scheme. In all likelihood, it had to do with the survival of the young fish. Rivers and streams tend to offer more hiding places than open ocean, and the young have a chance to grow large enough to survive. The most familiar of these fish are the various species of salmon and Steelhead Trout. I had several opportunities to view the November migration of the Chinook Salmon this week on three different rivers: the Mokelumne, the Tuolumne, and the Stanislaus.
In historical times, the fish ranged far into the interior of the Sierra Nevada and Cascades Range, being stopped only by cascades and waterfalls too high for them to jump. They numbered in the millions. As European and American colonizers replaced the Native Americans across the state, the fish began a steep decline.

One of the first and worst events was the Gold Rush of 1848. Miners tore up miles and miles of river gravels and disrupted the flow of the rivers with their placer mines (sluices, long-toms, and cradles). Hydraulic mines (water cannons) ripped away billions of cubic yards of gravels from the hillsides and choked riverbeds with egg-smothering silt and clay. Vast amounts of water were diverted from river headwaters to feed the hydraulic mines through a system of flumes and pipelines.

Somehow the fish survived this onslaught, but then something more insidious happened. The dam-makers arrived in the late 1800s and early 1900s to build reservoirs to divert water for irrigation purposes. The dams themselves were barriers to the upstream movement of the fish, but even worse was that water diversions left the rivers to small and warm for their survival. The mega-dams were constructed in the 1960s and 1970s, diverting even more water. One river, the San Joaquin, ceased to flow most years over a stretch of about sixty miles. By the time the last dam was built, more than 95% of the historical breeding grounds for the fish had been made inaccessible to their migration (see the map below).
The blue portions of the rivers have salmon. The historical range is shown in black. Source:
Millions of years ago, this landscape was much different. The Sierra Crest was lower than it is today, but the summit region was covered by volcanic complexes not unlike the Lassen Peak complex and other parts of the Cascades. Periodic eruptions sent steaming lahars (volcanic mudflows) down the river canyons and onto the floor of the Great Valley (which may have actually been a shallow sea in this area). The rocks from this time period, 5 to 12 million years ago, are called the Mehrten Formation and they can be found throughout the Mother Lode foothills.

The Mehrten Formation has yielded up a treasure trove of fossil species. At Turlock Lake fossils were found of Giant Tortoises and Oncorhynchus rastrosus, the Spike-toothed Salmon. These remarkable salmon were as long as eight feet. They apparently used their "tusks" to fight for territory. Otherwise their lives were similar to the salmon of today. The riverbanks were populated by horses, camels, bison, antelope, giant ground sloths, mastodons, and carnivores, including the ancestors of the bears and wolves. The woodlands were dominated by sycamore and oak. For an excellent overview of the fossil record, check out the technical article by Sankey, Biewer and others, or read their excellent book The Giant Spike-Toothed Salmon and Other Extinct Wildlife of Central California.
Oncorhynchus rastrosus, the Giant Spike-toothed Salmon. Artist: Jake Biewer

Erosional processes steal nutrients from the land and carry them to the sea. It has been remarked that salmon and other anadromous fish return the gift. After they fight their way up the streams and rivers, and after they lay and fertilize their eggs, the fish die. Their bodies provide food for a host of carnivores and scavengers. Long before I found any fish in the Mokelumne River the other day I sensed the lurking presence of several dozen Turkey Vultures. I wasn't actually thinking about fish at that moment, but wondered why so many vultures were hanging around the river.

Moments later the reason was clear, as many were already feasting on the dead fish. The alert eyes that followed the movement of the fish are of an ancient lineage as well. Turkey Vultures are the most common of the avian scavengers, but their ancestors and Condor relatives patrolled these rivers millions of years ago.
These fish have survived for at least ten million years, and it has taken only a century and a half to threaten their very existence. Even now intense controversy follows the negotiations over how much water to devote to agriculture and how much to preserve the future of the salmon and the entire ecosystem that they inhabit. It's not a fish versus people proposition as some have portrayed it. It is a larger question of whether we want to preserve healthy river habitats for clean water, a diverse ecosystem, and for our own recreation and inspiration. Agricultural interests in the drainage of the San Joaquin showed in the 1940s that they were more than willing to destroy a river to apportion every drop of water. Things began to change in the 2000s as agreements were reached to restore flows to the lower river and bring back viable populations of Chinook Salmon. I hope we can be as wise in the other water conflicts around the San Joaquin Valley.

These videos are from the Mokelumne River below Camanche Reservoir, the end of the road for the Chinook Salmon. I had never visited the area before, so I was exploring the trails at the day use area below the fish hatchery. There were lots of fish in the river, and large numbers of them were struggling to break through the gates of the fish ladder, which was closed. I followed the fish ladder into the hatchery grounds, wondering if it actually provided access to the reservoir, but it didn't. It led to holding ponds that were already full of salmon. When the fish are ready, the eggs are harvested and fertilized, providing the stock for the hatchery. The young fish are later released into the river at the hatchery and other locations downstream.

These hatcheries are one way of dealing with the devastating loss of habitat for the salmon, but it seems it would be better if we could provide access to their ancestral breeding grounds upstream. I don't claim any expertise in these matters, but there have to be better answers than what we see happening today. They've been here for at least ten million years, and deserve a chance to be around for a few more.

Saturday, November 10, 2018


And you know the sun's settin' fast 
And just like they say nothing good ever lasts 
Well, go on now and kiss it goodbye but hold on to your lover 
'Cause your heart's bound to die 
Go on now and say goodbye to our town, to our town 
Can't you see the sun's settin' down on our town, on our town 

Our Town, by Iris Dement

I'm heartbroken over the tragedies unfolding around my beautiful state.

I snapped this photo from a Home Depot parking lot near Modesto. Paradise is a long distance from us, but the smoke moved south very quickly, darkening the evening sky to the west. We've been hit hard this year by these fast-moving wildfires and we are long past when the winter rains should have arrived and put an end to the fire season. It's been savage.

Help out if you can. We've only got each other.

Charity Navigator:

American Red Cross:

Friday, November 2, 2018

I Went Rock Collecting Today...For Really, Really Big Rocks

I'm thinking how many times I've been on a field trip looking at a massive boulder composed of some kind of interesting rock and making a joke about how we would need a crane to get the thing back to school. I'll be darned if that very thing didn't come true today.

I was up in the Sierra Nevada foothills, choosing out some really big rocks, and we may very well be using a crane to move them back to campus. At least one of them weighs about 3 1/2 tons, and in total there will be about 60 tons of them. So yes, maybe my rock collecting habit has gotten out of hand. I need professional help.
Well, I might need professional help for something, but it's not for a colossal rock-collecting habit. I was selecting rocks representative of the geology of the Sierra Nevada foothills to become part of the landscaping of our new Great Valley Outdoor Nature Lab that is being constructed right now adjacent to the Great Valley Museum at Modesto Junior College.
At this particular quarry near Knight's Ferry on the Stanislaus River I was selecting boulders of Table Mountain latite (a volcanic rock broadly similar to basalt). These are the rocks that make up the dramatic inverted stream that winds its way among the towns of Sonora and Jamestown along Highway 108. I was also picking out some large granite and greenstone boulders to representing the bedrock found in the Sierra Nevada. We'll also be choosing some of the unique metamorphic "tombstone" rocks that stick out of the ground across the Mother Lode.

Meanwhile back on the campus of Modesto Junior College the outdoor nature lab is starting to take shape. We live in a flat valley, but the lab will have some topography, some small hills at the east end to represent the foothills. They will be planted with native trees and shrubs, and the trails and pathways will be lined with the rocks and boulders that we selected today. One of these days, the lab might look something like the scene below (which is actually at the quarry; they're showcasing what can be done with their rocks). It's incredible that the lab is finally happening. The science faculty at MJC have been fighting for an outdoor lab for three decades. It's been hard to be patient!