California's Precious Disappearing Prairies: A trip to the Willms Road Pond

One of California's precious landscapes is being lost, again. The state once had a vast prairie extending for 400 miles from Redding to Bakersfield. The grasslands were of course put to the plow, and agriculture rules the environment today. Less than 5% of the original grasslands of the Great Valley remain, and they've been under renewed assault in just the past few years.

The problem is nuts, and specifically almonds. The valley and nearby hills produce 80% of the world's supply, and they constitute the largest agricultural export we produce right now. The trees use prodigious amounts of water, but that hasn't stopped a vast expansion of the orchards into the remaining prairies on the east side of the valley where the Sierra Nevada foothills begin. With a crippling drought and no reservoir irrigation possible, the landowners are simply drilling wells and pumping the water from the ground. The supply of groundwater is limited and in severe decline. I am pretty sure these wells cannot provide more than a few year's worth of water before they'll be dry.

Still, the prairies aren't gone yet, and I took a break from taxes this weekend to catch the sunset from Warnerville and Willms Roads east of Oakdale. We drove through miles of newly planted orchards, and into some of the grazing lands beyond. It was a stunning reversal from the appearance last year of dead grass and dry streambeds. We've had adequate amounts of rain on the valley floor, with upwards of 10 inches in December, and a few good storms in February to make up for a record dry January. The grass was green and growing, and the ephemeral streams and vernal pools were filled with water. We just need more snow higher up in the mountains to get well from the drought, as the snowpack is less than 20% of normal right now, with the end of the rainy season looming.

We were following on the heels of an unusually active thunderstorm system. Our weather is pretty benign most of the time, but this storm dropped upwards of a foot of snow in the high country. The clouds were an incredible sight in the last glow of the dying sunset.

There were animals out and about. The Western Meadowlarks were present in large numbers, trying to attract some mates. They have a most beautiful song, which I captured on a brief video that you can listen to at my Geotripper's California Birds site (click here).

The story was the same with the Red-winged Blackbirds. There were dozens, if not hundreds, at our favorite little stock pond on Willms Road. They were strutting about displaying their bright red and yellow shoulder patches.

If some of the smaller animals weren't paying careful attention, they might not have noticed the hawk lurking in the almond trees. I almost didn't see it myself as we passed.

The biggest surprise came as we passed the small cliff along the creek that crossed Warnerville Road. I was expecting or hoping to see some burrowing owls, but the biggest hole was occupied by the raccoon seen below. When it noticed us, it just up and disappeared into the burrow.

The remaining prairies have persisted because no one could think of how to make money from them other than grazing cows or sheep. Now that almonds are a lucrative source of money, there is a target painted on the ranchlands in the Sierra Nevada foothills. I hope the state gets around to writing the groundwater regulations so we can get a handle on the unrestrained development that is taking place right now. It's clearly unsustainable in the long run.

Springtime on the California Prairielands: An Update (and gratuitous baby horsie pictures)

We went out to investigate springtime in the California prairielands, up around the margins of the Central Valley just short of the foothills of the Sierra Nevada. There is a pretty sharp demarcation of spring and summer in this Mediterranean climate; the subtropical belt of high pressure shifts north and shuts off the rains coming out of the north, bringing higher temperatures. All the sudden it is dry and hot for six months or so, almost without exception (the exception being the occasional tatters of a hurricane out of Baja California). In those warm days of springtime there is an explosion of life on the grasslands.

The first picture above shows a vernal pool (or a very good representation of one; there were railroad tracks nearby that may have dammed the swale). Vernal pools develop on the very old alluvial fan surfaces of rivers that flowed from the Sierra during the ice ages. The muddy rivers spread all over the plains, but when the glaciers melted away the rivers started flowing with clear water. The faster moving rivers carved deep channels and narrow floodplains that they have occupied for the last 13,000 years. The surfaces above the floodplains are pockmarked with numerous small basins with small interior drainages (caused by wind deflation or differential settling of the soil). The basins are lined with clay that causes water to pond instead of sinking into the soil. The vernal pools are an ecosystem pretty much unique to the Sierra Nevada foothills.

You can see a fairly sharp delineation in the vegetation at the edges of the pools. The normal grasses don't do as well being inundated with water for a few weeks in the spring, and being rooted in solid clay. A number of plant and animal species have evolved to thrive in the unusual environment. The vernal pools have been decimated by urban and agricultural development; they were a major issue during negotiations for the siting of the University of California Merced campus. The one we looked at was in a pasture and had been heavily trampled by cattle.

A lot of flowers were visible. It's pretty amazing that I can identify dozens of minerals without breathing too hard, but I have a mental block when it comes to any flower called something other than Poppy or Lupine. I'm guessing that this beautiful small blue, white, and yellow flower is a Bacigalupi's Downingia, based on a highly sophisticated internet picture search (looking at pictures is one of those things I tell my students not to do when identifying minerals; look at the properties, I say).

I'm a little more sure that the yellow flowers above are Goldfields (Lasthenia californica). There is also some Owls Clover spread along the Goldfields (below). It took a few moments for me to notice the birds perched on the cobbles among the flowers. I am assuming they are juvenile Western Meadowlarks, but I welcome any corrections! I'm about as good with birds as I am with flowers...

I would also welcome an I.D. of the hawk that was soaring above us. I'm afraid I'm flummoxed by any hawks or eagles that don't have red tails...

The prairies that I have come to value so much in recent years are clearly under a threat. For decades the lands have been used for grazing (for better or worse), but as more and more of the prime agricultural lands in the valley have been urbanized, the farms are moving towards the less favorable soils of the foothills. I was shocked by the sudden appearance of hundreds of acres of newly plowed and planted orchards and vineyards.

As promised, there were horses roaming the grasslands, and the mares had recently given birth to foals (I say this because I know Diane and Jennifer, my horse-loving friends, will be all up in arms over the title of today's post). There is an interesting geological connection between the horses and the land here. Most of us know that horses arrived in the "New World" with the Spaniards in the 1500's, but fewer know that the horses were coming home after a fashion.

The ground beneath the feet of mare and foal contains the occasional fossil teeth of horses. Some of the fossils date from as recently as 12,000-13,000 years before the present, the time at which the horses became extinct in North America. Other fossils in older rocks beneath are of smaller horses with different teeth and extra toes. The horses evolved in North America, and there have been dozens of species found as fossils (compared to the three that we have today). Some of them migrated over the Bering Land Strait and thrived in Asia, but they eventually went extinct in America, for reasons that are not clear.

They were a beautiful sight the other day...

The Other California: Back on the Prairielands

I started my Other California series last year with a post on the little-known and under-appreciated prairielands of the state, a vast landscape surrounding the Central Valley (and which once was the Central Valley in the days before agricultural development). When I conceived of the idea for the prairielands posts, I was in the Sierra Nevada foothills in late fall when all was dry and barren. I revisited the original site today to witness a different world, one that was green and full of life.

The soils in our part of the Sierra foothills are underlain by andesitic mudflow (lahar) deposits that poured off the higher mountains around 9-10 million years ago. The hills in the distance (and around the lake below) are metamorphic rocks of the Foothills Terrane, dating from around 200 million years ago.

We had a reasonably decent rain season, with close to 100% of average precipitation. We really needed about 120% to overcome the three years of drought, since many of the soils around the state are exceedingly dry and need to be replenished, but on this day there was plenty of water in evidence in the normally dry creekbeds and stockponds. One of our favorite stops is a little lake on Willms Road in the vicinity of Knights Ferry on the Stanislaus River. Vast numbers of birds are usually in evidence.

Since getting my first digital camera 9 years ago, I have concentrated on geological subjects, but I have been adding more plants and animals to my repertoire. There is an old adage about geological field work, that you will spend an entire field season collecting every unusual and unique rock in sight, and later come to the realization that you never collected a single specimen of the most common rock in your study area. My bird pictures are kind of like that. I have few pictures of the most common birds in our area.

The fuzzy picture above is my first photograph of a Western Meadowlark. They were very much in evidence, as their calls could be heard every place we stopped, but they were shy about being approached, so this one was taken with a 30x zoom (lest you think I have sophisticated equipment, that is optical and digital zoom together).

The second bird shot is the exceedingly common and obviously-named Redwing Blackbird. These were a couple of guys hanging out, hoping to pick up some ladies. The females are decidedly not well-named, being more drab brown without the red wing spots.