Monday, June 10, 2019

Every Place Has a Story: Prichard, Oregon's Smallest State Park

I've been visiting Florence, Oregon for a number of years, and it is a beautiful place. The Siuslaw River reaches the sea near the town and at the northern edge of the Oregon Dunes National Recreation Area. Sea Lion Caves lie hidden in the coastal cliffs just north of town. But Florence holds one other distinction: it has Oregon's smallest state park. It's called Prichard State Wayside, and it totals an entire 0.5 acres. To be sure, Prichard is not the smallest park in Oregon. That distinction belongs to a city park in Portland called Mills End Park. It's located at in intersection in the city, and has a total area of 452 square inches.

A visit to Prichard State Park is not exactly a life-changing event. The half acre includes a grassy swale, a couple of trees, a small parking area, and no facilities at all. There's a single sign identifying the site. There's no interpretive signage, and little information on the internet about the history or genesis of the park. I'm guessing it was some land that was donated to the state, and the officials that be couldn't really decide what to do with it.

Looking at the park, I was reminded of something that I tell my students on the opening day of every class: geology is where you find it, and every place you find has a geological story. At first glance I was hard put to imagine an interesting geological story for this place. But a moment's reflection proved the opposite.

Let's take a look at the setting of the park. It is a grassy slope that is situated along the Siuslaw River, which from this angle looks like a huge body of water. But it isn't technically a river. It's a tidal estuary, and the wide body of water flows either downstream towards the sea or upstream in response to the daily tides. In a few hours the entire mudflat in these pictures will be covered with water. The area of tidal influence extends 26 miles inland, which is nearly 20% of the entire length of the river. Upstream of the tidal influence, the river is modest, with an average flow of about 2,000 cubic feet per second. That's less than a third of the more familiar Rogue River.

The story of any part of the Earth starts with the rocks that underlie the site. A quick look at the geological map of the park region shows that the "bedrock" is composed of "Qal", translated as 'Quaternary alluvium". Alluvium is our term for any of the loose sediment that covers the more solid rock underneath. "Quaternary" is the last little gasp of geologic time, encompassing the last 2 million years. The unit might include the mud of the estuary, river and or gravel, or dune sand. The Qal at Prichard is most likely slightly consolidated dune sands, which is a material that underlies most of the coastal areas in the vicinity of Florence. Sand carried along the coast by wave transport is blown inland by persistent onshore winds, forming the dunes for which Oregon Dunes National Recreation Area is justly famous.
The picture above shows the coastline just north of Florence. The region has undergone a significant change in the last hundred years or so. Migrating dunes can certainly be a problem in developed areas, so a European species of beach grass was introduced in the 1920s in an effort to stabilize the dunes. The grass worked too well, and sand has been trapped in the area adjacent to the shoreline, building into an ever higher ridge of grass-covered sand. The area inland has been starved of sand, so it has blown farther inland, leaving a low area called the deflation plain, a region now covered by small ponds and scrubby forests.

Sand is a famously unstable foundation for buildings (it's even in the Bible), but dunes that have been stable for centuries or millennia will sometimes be consolidated by calcium carbonate or other minerals in the groundwater. That is a much firmer surface to work with, and thus the development of the Florence area has been possible.

Going back in geological time often leads to strange changes in the appearance of the landscape. For instance, during the ice ages of the last 2 million years this little park would have looked far, far different than it does today. It's not because there was any ice; the glaciers that were present in Oregon were many miles away up in the Cascades. The big different was sea level. With so much ice locked up in the vast continental glaciers that covered almost all of Canada and northern Europe, sea level dropped to around 300-400 feet lower than today. Prichard State Park a few tens of thousands of years ago would have been perched on a terrace above a Siuslaw River ensconced in a deep river gorge hundreds of feet below. The outlet of the river would have been miles to the west of where it is today. 

One last aspect of the geology of any region is how it affects those who live there. Hazards present at Prichard would clearly include flooding and fires (especially in a time of global climate change). As noted earlier, the average flow of the Siuslaw River is about 2,000 cubic feet per second. The record flood on the river was around 45,000 cfs, and in that circumstance, the water would rise to inundate the little park.

The other very serious threat is that of tsunamis. These destructive surges of water could be developed by a massive earthquake on the Cascadia Subduction Zone that runs parallel to the coast. A quake has now been documented as having reached magnitude 9 in 1700. Such an earthquake is thirty times more powerful than the magnitude 8 quake that devastated San Francisco in 1906, and around a thousand times more powerful than the 1988 Loma Prieta earthquake (just short of magnitude 7). Tsunamis can also be generated thousands of miles away in places like Japan or Alaska. Whether local or distant, Prichard State Park would be a dangerous spot if a tsunami ever hit. There would be no "breaking wave" as is shown in many photoshopped images. The water instead arrives as a surge moving rapidly upstream at high speed. In moments, the park would be inundated to a depth of several tens of feet. The water would eventually recede, but then a second, third, and maybe fourth wave will follow.
Geology is everywhere, and everywhere has a geologic story, even Oregon's smallest state park. Check it out, if you can find it!

Wednesday, June 5, 2019

The Great Valley Museum Outdoor Nature Lab Stands De-fence-less!

Something special happened yesterday at Modesto Junior College and the Great Valley Museum. The Outdoor Nature Lab, which has been completely fenced off for most of the last year became "de-fenced". The construction process has not been finished, but the basic structures, the rocks, the plants, pathways, greenhouse, and irrigation/lighting are in place, and visitors are now able to wander through the newest addition to the Great Valley Museum.
The picture above is how the site looked in January shortly after the fencing went up. The field had been barren for three or four years after the construction of the Science Community Center. Some in the administration had wanted to plant the field with grass while we waited for the funding of the Outdoor Nature Lab to be approved, but the faculty and staff of the Center resisted. We were aware that it would make it easier for the funding to "disappear" if there was a nice grassy area. We chose to have a barren lot. The funding was precarious, as the lab was one of the final projects to be funded by our Measure E bond from a decade ago, and a cost over-run in other areas could have eliminated the project entirely.
The parade of constantly changing administration officials who had occupied their offices for only a few years sometimes had trouble understanding how important the Outdoor Nature Lab was to the museum and faculty at Modesto Junior College. It has been a dream for more than three decades that we would have a microcosm of the Great Valley natural environment adjacent to our facilities, with the native plants and characteristic rock types (as well as a greenhouse and demonstration gardens). Many of our students and visitors have barely ever traveled outside the city limits and are unaware of the incredible world that still exists in the corners and edges of our valley.
We were thrilled yesterday to find that along with the disappearance of the fencing that some of the natural environment was already arriving to occupy our small natural landscape. Killdeers were wandering over the site, and we suspect there might even be a nest nearby. The Killdeer is the mascot of the museum and center, appearing on our logos. It seemed a good omen, like a blessing.
Spring is still going on at the outdoor lab as well. There were delays with the planting so the worksite missed any kind of natural wildflower blooms back in March and April, but we have a great many newly-planted trees, and they will have to be irrigated until they can mature and put down an adequate root system. Natural wildflowers were also planted, and they are blooming right now.

Pathways wander throughout the lab, providing a serene place to walk or wait between classes, especially as the trees grow and mature. Interpretive signs will be installed soon that explain the identity of the plants and rocks, and the relationships that make up the Great Valley biome.

Part of my role in the design of the lab was the selection of rocks that we chose to represent the lower foothills of the Sierra Nevada. I was able to select somewhere around 30 tons of boulders that now crop out in the eastern part of the lab.
At the north end where visiting students will disembark from their school buses, we've placed boulders of the Table Mountain lava flow. It is a relatively rare rock called latite, but being black, and originally highly fluid, it can be thought of as a form of basalt. The lavas emerged from vents located today high in the Sierra Nevada near Sonora Pass (the Dardanelles) and flowed west for nearly 60 miles to the Knight's Ferry area. As the mountains later rose and tilted west, erosion removed the rocks from around the lava flow, but the lava flow resisted the forces of erosion and ended up as a ridge that retained the sinuous path of the ancestral Stanislaus River.

The boulders are covered by a veritable ecosystem of lichens and mosses. When I picked them out last October, they were drab and dried out. When the rains came the surface of the rock came alive with color. It's a marvelous place to see the weathering of rock and formation of soil happening right in front of your eyes. The lichens produce acids that slowly break down the rock into clay and nutrients.
At the south end where students will be walking into the museum, we've placed "tombstone rocks". These are some of the oldest rocks found in our region, metamorphic slate and phyllite that started out as mud and silt on the bottom of the Pacific Ocean. Plate motions carried these sediments into the subduction zone that once extended from Canada to Mexico. The sediments were scraped off the ocean crust and added to the edge of the continent. In the process, the mud and silt were subjected to intense heat and pressure, and they were tilted to a vertical position. Differential erosion removed the softer layers, leaving the harder slabs to stand out like a ill-kempt cemetery plot.

Other rocks on the "upper" trail include marble boulders, the host rocks for the Mother Lode's spectacular caverns. We also have a huge chunk of quartz, the host ore for the gold that was responsible for the most transformative events in the human history of California, the Gold Rush of 1848.
In a few months we expect to see a scaled-down model of a Saurolophus, the first dinosaur ever to be found in California, erected in the barren area on the lower left corner in the picture below. It was discovered by a teenager named Al Bennison in the 1930s right here in Stanislaus County, up in Del Puerto Canyon. Few of our children are ever taught about the rich paleontology of our valley and the many kinds of fascinating creatures that used to live here in the valley, including Mosasaurs, Plesiosaurs, Hadrosaurs, and in much younger rocks, Sabertooth Cats, Mammoths, Short-faced Bears, Giant Sloths, and Dire Wolves. To help their imaginations, we are installing a mock paleontology dig at the western end of the nature lab.
It's an exciting time for our faculty, staff, and volunteers. It's not complete, but for the first time we are able to wander about this wonderful little microcosm of the Great Valley. For some of us it has been a three-decade wait, but it's been worth the effort. A lot of people have worked very hard to make this unique educational experience a reality.

Sunday, June 2, 2019

Darlingtonia: A Horror Story in Sand and Serpentine: Part 2, the Sequel

Those "forked appendages" that look like they're reaching out for hug? Don't fall for it, it's a horrific trap!

In horror movies, we all know the monster/murderer is never dead, and that there is always a sequel. In that spirit, I am revisiting a blog from 2013 about Darlingtonia californicus, the carnivorous plant that lives in acidic or serpentine-based soils in northern California and Oregon. My last visit was during a November, so I missed any blooming flowers from the plants. This time, it was spring and I got pictures of the unique flowers of the Pitcher Planet (or Cobra Lily). They're towards the end of this post. Let's get to the story...
The trail through the forest began innocently enough. Greenery was everywhere. The travelers were hungry, driven by a need for food, a need so bad they could smell it. They drove deeper into the dark shadows. They began to be aware of a pervasive odor, an odor that awakened memories of delicious feasts from the past. Something was out there in the dark shadows.

There was an opening. The splendid odor of food wafted from inside. They were so hungry, they were driven to see what was in the opening. There were some strange fibers about their feet, but the smell of food was overpowering their sense of caution. They crept further inside, becoming vaguely aware that the floor beneath their feet was becoming slippery. The entrance was now out of sight, but they didn't worry, they could see openings that would allow them to escape if necessary. They started sliding deeper into the cave, and they became alarmed. They decided they were in danger, and climbed towards the openings only finding to their increasing panic that they were transparent windows, not exits. They could not escape! Where was the opening? It was gone. 

A pool appeared below. A pool filled with the digested remains of previous travelers. The travelers realized their peril and tried to climb back up but downward pointed spikes prevented them from doing so. They struggled, exhausting themselves as they fell deeper into the abyss...
And such is the terrifying drama that was recommended to me by Lockwood when he found I was headed to Florence, Oregon for Thanksgiving back in 2013. Of course the travelers were insects, not humans, and their terrifying trap was a Darlingtonia californica, also known as the Pitcher Plant or the Cobra Lily. The plant grows in northern California or southern Oregon, in two completely different environments: sandy coastal bogs and serpentine soils. In both environments nitrogen is limited and the plants get it by capturing and digesting insects.
They're looking at you...
The Darlingtonia Botanical Wayside is a small parkland of 18 acres about five miles north of Florence, Oregon in a bog formed in the hollows of coastal sand dunes that have been stabilized by the growth of a thick forest. It's a pleasant little stop, and given the nature of the plants in the bog, maybe free of mosquitoes? Maybe not at other times of the was pretty cold the first time we were there. Yesterday it was windy.
They're discussing you...
It was November when I visited the first time. We were there on the last day of May this year, and the flowers of the Pitcher Plants were blooming.
The plant is a real conundrum. On the one hand it attracts bugs in order to pollinate the plant, but on the other it tries to consume them!

The trail is short and handicapped accessible, and there are several interpretive signs.
They're all looking at you and sizing you up. Be scared. Be very scared...
The small section of forest in the park was also beautiful. I haven't been in the area enough to start recognizing the species just yet. Cedar or spruce?
If the Darlingtonia doesn't get you, maybe the tree trolls will instead...

Sunday, May 26, 2019

What to do on a Saturday? Let's Go to the Middle of the Earth (via Del Puerto Canyon)!

The strange and alien landscape in upper Del Puerto Canyon.
California has some really strange landscapes. A state that has beaches, mountains, volcanoes, forests, and deserts is going to offer many perspectives of the complex geological influences on the state. But for alien and otherworldly, few places in the state can compare to the journey you take when you follow Del Puerto Canyon from its mouth in the Great Valley to the headwaters in the Diablo Range. It's a journey into the middle of the world. Our Geology Club made the trip a few weeks ago as an ending of the semester celebration. Odd way to celebrate? Did you simply party? We traveled half-way to the center of the planet!
"Del Puerto" refers to "The Gate", the constriction of hard sandstone at the mouth of the canyon.
I guess I should be a bit more specific. We journeyed to rocks that had once been part of the Earth's mantle, the 1,800 mile thick layer that lies just beneath the thin crust (3-50 miles thick). We couldn't reach the core of the planet, because no one can (despite sci-fi movies that say otherwise). Since mantle rock is very hot and is subject to convection, it is at least conceivable that the rocks we explored had once been close to the Earth's core.
So how does one explore the Earth's mantle? Well, first one has to get through the crust, and the thinnest crust is that which makes up the ocean floors. It's nominally composed of basalt, but the details are more complex.

In Del Puerto Canyon, the ocean floor is covered by...a bit of sediment. About 25,000 feet of it! The sediments poured off the mountainous edge of the continent during the later part of the dinosaur era, the Cretaceous Period. There was a huge subduction zone that formed as oceanic crust plunged into the mantle beneath the edge of the North American continent. This so-called Cascadia Subduction Zone caused volcanoes to form where the Sierra Nevada is today, but the area offshore of the volcanic arc, the forearc basin, collected sediments. As the sediments accumulated, they pressed the crust downward and even more sediment piled on top. Eventually the layers reached a thickness of five miles.

The basin collected fossils as well. There were the usual shells of clams, snails and ammonites, a variety of shark teeth, and three groups of seagoing reptiles, the plesiosaurs (think Loch Ness), ichthyosaurs (think reptilian version of a dolphin), and 35-foot-long mosasaurs (think "swim for your life!"). Even dinosaur fossils have been found. The first dinosaur ever found in California, a Saurolophus, was discovered in the lower reaches of Del Puerto Canyon in 1935.

Eventually, one will reach the base of the oldest sediments, and encounter the ocean crust itself. Faulting obscures some of the relationship, and so in the picture below we see some of the oldest sediment on the right (somewhat brownish shale) and basaltic/andesitic volcanic rock on the left (greenish gray), separated by a fault. The volcanic rocks are harder, and the canyon takes on a more rugged aspect as we climb higher into the mountains.
The Coast Ranges of California are one of the youngest mountain systems in the world, having been uplift mostly in the last 3 million years or so. The streams in this dry environment have not been able to downcut as fast as the mountains are rising, so they flow much of the way over bedrock. There are few floodplains in these mountains.
The water flows almost year-round and thus the canyon is a critical habitat for all kinds of wildlife. Dozens of mammals and reptile species are known, and nearly 200 bird species have been observed here.
Oceanic crust is basaltic in composition, but there are differences at depth. On the ocean floor, basalt flows form "pillows", globular masses of the volcanic rock. Beneath the pillow basalts, basaltic dikes fed the eruptions. Dikes occur when volcanic rock fills cracks and fissures in the surrounding rock. Since the surrounding rock is also dike material, the entire layer, a mile or two thick, is made of vertical sheet dikes. Feeding these dikes were magma chambers composed of...basalt! But some of the basalt was left at the base of the oceanic crust where it then cooled slowly to form a sparkling crystalline rock called gabbro. The entire suite of rocks is called an ophiolite sequence. The Coast Range Ophiolite sequence in Del Puerto Canyon is considered to be the second best exposed in the state, behind the Point Sal Ophiolite in southern California.

We stopped in one of the most rugged parts of the canyon to investigate the gabbro where it was pierced by a vein of quartz (below). People have looked for gold here, but I doubt they found any.

Just a few more miles up the canyon and we penetrated the uppermost part of the mantle. The rock originally consisted of ultramafic minerals like olivine and pyroxene, but here the rock has been metamorphosed into serpentine, California's state rock. The rock was sheared and faulted on its way to the surface, leaving shiny green and black polished surfaces (below).
And then we were there. In the uppermost part of the canyon, we reached the netherworld of mantle rock that was far less altered, so that it retained some of its original appearance. In places we could see olivine and pyroxene crystals, as well as grains of chromite. These ultramafic rocks contain few nutrients needed by plant life, so only a few species can tolerate living on these slopes. Gray pines are among them, grasses generally are not. There are a number of wildflower species endemic to California that can be found here.
Looking at these shattered broken rocks from very deep in the Earth, one imagines hell freezing over. The forges of the demons and devils lie frozen in place, to be slowly removed by earthly weathering. They tried to invade the surface realm, but they were defeated by the forces of the heavens, the water and ice falling from the sky.
It may have been a metaphorical battlefield, but in the end there is great beauty in the rarity of the flowers, plants and animals that thrive, or at least tolerate the conditions in the upper canyon.

We turned around and headed back to more familiar habitats.

Del Puerto Canyon is traversed (slowly) by Highway 130, originating in Patterson on the floor of the
Great Valley. It can also be reached by way of Mines Road out of Livermore, or  a winding road out of the San Jose area over Mt. Hamilton and the Lick Observatory complex. It is not a fast way to go!

Saturday, May 18, 2019

The Eruption of Mt. St. Helens at 39 Years: Why It Still Matters

It is the 39th anniversary of the famed eruption of the St. Helens volcano and as I think of those days, I realize that even though a majority of the population wasn't even alive at the time, the volcano still matters. Not because of the potential for future eruptions (although that remains a distinct possibility), but because of the way we process and deal with the natural hazards that we all face, no matter where we live.

When the volcano began rumbling and sending ash into the atmosphere, we had only a few avenues to get information, mainly television news, radio, and newspapers. I think now how limiting these sources were compared to the nearly instantaneous delivery of news over the internet in the present day. We can look up earthquakes just moments after they happen, and webcams allow us to monitor volcanoes around the world in real time. There is both good and bad in this profound change. There were terrible sources of news in those olden days, like the Weekly World News or the National Enquirer, but they pale in comparison to the sewage found on the internet today. Back then, national news outlets and newspapers practiced careful journalism in most instances, but it often seems today that the only reward for excellence and honesty in reporting is decreased ratings and falling revenues. To get attention in a crowded internet environment media outlets have to dress their stories in shiny objects and provide them with the worst possible clickbait titles. In the olden days we often had to wait impatiently for information about natural disasters, but the information that came through the media was more often vetted and checked for accuracy. The journalistic filters today are completely gone, and it can be difficult to distinguish between the trash and the truth.

There are so many conspiracy theories floating around today about natural disasters and potential disasters. The eruptions of Steamboat Geyser in Yellowstone National Park numerous times after years of quiescence has caused a blizzard of posts on the internet pondering whether Yellowstone has been disturbed and may blow as a "supervolcano" eruption soon (and we'll all die). The same has happened after a number of recent small earthquakes. But a reading of the reality-based data says that Yellowstone caldera has not had a lava flow or eruption of any kind in 70,000 years, and no knowledgeable geologist sees any evidence of precursors to any new eruptions. A few years back, an earthquake and an internet video of a group of bison running "away" from Yellowstone caused the same kind of internet speculation (it turns out the bison were running towards the caldera).

Of course it is true that the Yellowstone caldera was born in one of the most colossal eruptions ever recorded. Learning the story of the eruption of the Huckleberry Tuff is fascinating. It brings an entirely new appreciation of the incredible scenery to be observed in a place that contains 70% of all the world's geysers. It should be enough. But there are so many individuals out there who would like to make a buck by scaring people needlessly. And there are too many gullible and ignorant people out there who can't pick rational accounts out of the confusing mix of conspiracy theories that exist on the internet.

And then there is the Big Island of Hawai'i. There were some serious and tragic things going on last summer as the longest eruption in history reached a climax. The activity endangered lives and destroyed homes as Kilauea underwent major changes from the "norm" of the eruptions that had been ongoing for the last 35 years. The U.S. Geological Survey and Hawaiian civil defense authorities did a pretty good job of providing up-to-date information about the latest activity, but that didn't stop all kinds of stories from popping up on the internet about the "Ring of Fire" which has nothing at all to do with Hawai'i. It was just too easy to pick up stories of eruptions in Alaska and Indonesia and think there was a pattern of increasing volcanism or earthquake activity (OMG, a magnitude 6 quake in the Kermadec Islands and an eruption at Mt. Cleveland in Alaska! It's a pattern and therefore Seattle will fall into the sea very soon!). The problem is one of perspective: if you had signed up for earthquake notifications and volcano advisories from the USGS or other geologic research institutions, you would have realized that these things happen all the time, and that a cluster of events is not unusual.

It's one thing to make up stories about normal volcanic activity to scare people. One can argue that they are ultimately harmless because the eruptions aren't actually taking place or hurting anyone. But there are real-world consequences of ignoring journalistic standards. Many of those who make their money with false headlines about such things will also traffic in climate change denial. When science becomes a matter of believing whatever one wishes, the very real problem of global warming becomes just another "scare" story, and the alarm bells being sounded by climate scientists become just more noise in an internet full of noise. But the real-world consequences are happening now, and action is needed to counteract the changes or to stop them. But it has become too easy to ignore the problem because it is so incremental and slow-acting. It just can't compete with the shiny baubles and clickbait on the web.
People in Hawai'i mostly trusted the geologists who studied the volcanoes all their lives and thus made the correct decisions about evacuating homes and businesses. In the same way they trusted the seismologists when a tsunami threatened the islands in 2011 after the massive earthquake in Japan. No lives were lost when the tsunami hit because people had evacuated the low-lying areas. The wave surge was 8 feet deep in places and caused millions of dollars of damage. Many people could have been killed, but they accepted the authority of the scientists who predicted the timing and magnitude of the seismically induced waves.

And that's why the Mt. St. Helens eruption of 1980 matters today. Scientific expertise matters. Climate change is an even more profound danger to society than any earthquake or volcanic eruption. We need people to give climate scientists the same kind of respect they give geologists when volcanoes are rumbling and smoking. They are the ones to listen to, not the hucksters on the internet who are out to make a buck, or trying to protect those industries that make their profits off of producing greenhouse gases. We seem to talk little these days about integrity and striving for excellence, but scientific researchers are among those who still have those traits. There are always exceptions, but I would trust a scientist over a politician any day of the week (unless it is clear that the politician knows how to listen to a scientist).

There is a sign seen at some of the March For Science protests that have been happening for the last two years around the country: "At the start of every disaster movie there's a scientist being ignored". Unfortunately, it is too true in real life as well.

This has been a highly abridged and updated version of last year's St. Helen eruption anniversary reflection.

Tales from the Semi-Super Bloom Tour, Part 5: Coming Home

"We shall not cease from exploration
And the end of all our exploring
Will be to arrive where we started
And know the place for the first time.
Through the unknown, remembered gate
When the last of earth left to discover
Is that which was the beginning..."
T.S. Eliot
I'm a bit behind, what with the end of the semester and all that, but there was a bit of unfinished business from a few weeks ago...the end of our Semi-Super-Bloom tour. Yes, most of the flowers throughout the west have faded and shriveled as April turned out to be very dry. In this wet year many parts of California were covered by flowers in a way not seen in a decade or more. It was a spectacle and hundreds of thousands of people converged on places like Anza-Borrego, or Elsinore, or the Grapevine in Southern California. Among the crowds there were the stupid and ignorant who trampled the flowers and in one instance landed a helicopter in a field of flowers.
Around six weeks ago, Mrs. Geotripper and I set out to find some of the less crowded places, the spots where the flowers were blooming, but they weren't quite at the level of the Super-Bloom. Our journeys carried us through the Mojave Desert, Death Valley National Park, the Merced River Canyon downstream of Yosemite, and the Red Hills Area of Critical Environmental Concern. But it was our final journey of the tour that was so illuminating: we were home. And it was a beautiful place.
We live at a nexus point, the boundary between the Sierra Nevada and the Great Valley of California. Our town is surrounded by agricultural fields, but as we drive east, the fields and orchards give way to one of the few remaining prairies in the state of California. Although large portions are being plowed over for almond orchards, the grasslands still exist in the low foothills of the Mother Lode.
The soils are old and deeply weathered, and are generally nutrient poor. It's only a few feet to bedrock as a rule, so water is not often available for plant growth, and so for most of the year the hills are covered with a brown (some say "golden") veneer of dead grasses.  But in the spring of wet years, the prairie comes alive with color. One of the unique habitats of our grasslands are the vernal pools, the hollows where water stands for a few short weeks or months in the spring. Because they are flooded part of the year and dry for the rest, they are a crucible for the evolution of unique plants and animals adapted to the harsh environment. Many of California's endemic plants are found there. There are hundreds of these vernal pools scattered across the prairie. And that's where we saw much of the color as we drove through a few weeks ago.
We were traveling on Willms Road south of Knight's Ferry on the Stanislaus River when we spotted one of California's near-endemic bird species. Red-winged Blackbirds are a familiar sight across much of North America, but there is a closely related species called the Tricolored Blackbird that is mostly found in the Great Valley and in the prairies of the foothills (they have a white stripe below their red wing spots). The birds are endangered because of an unfortunate habit they have of nesting in large colonies in the middle of grassy prairies. The problem is that they don't make a distinction between a tall-grass prairie and an alfalfa field, and thus thousands of nests and their occupants have been destroyed in an afternoon as farmers cutting and harvesting the alfalfa. Efforts are being made to reimburse farmers who wait a few weeks to harvest, giving the young birds a chance to mature and fly away.

We were home, and we found exploring the back roads just beyond our backyard to be just as colorful and wondrous as our thousand mile journeys into the deserts and beyond. Never stop exploring, and never be trapped into thinking that you have to go vast distances to see wondrous things.