Saving California's Old-growth Grasslands

It doesn't take a PhD in Environmental Science to recognize that the loss of old-growth forests, such as California's iconic Coast Redwoods, is a tragedy with far-reaching consequences.  Many and varied are the champions of Spotted Owls and Marbled Murrelets.  

But what about California's old-growth grasslands, and the wildlife that depend on them?

Western Meadowlark: posterchild of the grasslands

No, "old-growth grassland" is not a term I just made up.  Scientists the world over are beginning to discover that the idea of old-growth grasslands is indeed a real concept, with very important implications for conservation.  

Rather than thinking of grasslands as just one successional community, a stage in the process of becoming a climax community, grasslands should instead be considered climax communities in themselves, rich in species diversity and endemism.  

In discussing succession, I am referring to something like the classic Ecology 101 example of a lake gradually filling with sediment until it becomes first a shallow pond, then a marsh, then a wet meadow, then a dry area of grasses and shrubs, until it is finally colonized by trees and becomes a mature forest.  The mature forest in this example is the ultimate climax community, while the meadow and grassland communities in between are just stages in the process of succession, ultimately destined to become something greater.  

While the relative age of old-growth forests is obvious, to an extent, from the sheer size of its trees alone, grasslands tend to be very slow-growing and the indicators of old-growth grasslands lay mostly buried, hidden in masses of roots and rhizomes.  But the indicators of a climax community are there.

Old-growth grasslands are ecologically distinct regions that, due to a number of factors including climate, herbivory and fire, have been grasslands for a very, very long time.  And, unless disturbed or developed by humans, they will remain grasslands for some time to come.  

For more on the concept of old-growth grasslands, take a look at this article.

Horned Lark

But let's pause for just a minute and answer one very important question:

What is so special about grasslands?

Aside from the intrinsic and aesthetic value of an intact ecosystem, grasslands provide a number of goods and services to humans.

Grasslands provide grazing land for livestock, especially cattle and sheep, which in turn provide us with meat, dairy, leather, wool and more.  In fact, well-managed grazing systems on our remaining grasslands contribute to the ecosystem's overall health, as well as to the economy.  Everyone benefits from sustainably grazed grasslands!

Like both freshwater and saltwater wetlands, grasslands improve water quality by filtering and storing water, as well as providing erosion control.  Water held by grasslands is able to slowly percolate back into the soil rather than running off.

Grasslands provide carbon storage, acting as carbon sinks, as carbon is removed from the atmosphere through photosynthesis and stored underground in root masses and thick layers of organic matter.

I mentioned the intrinsic and aesthetic value of grasslands, which is easily underestimated in a state bounded by awe-inspiring mountain peaks to the east and rugged sea cliffs to the west.  The middle bit, the hills and valleys covered in "dead brown grass" for most of the year, is easy to skip over.  

But grasslands are places of beauty too: wild, desolate, solitary beauty, places where winds blow and wildflowers glow in day after day of golden sunshine.  

Don't discount our grasslands, for they too offer stunning panoramas and thought-provoking vistas, dazzling wildflower displays, and mile after mile of quiet hiking paths for rambling and reflecting.

Grasslands at Carrizo Plain National Monument 

Then, of course, there is the habitat value of intact, old-growth grasslands.  73 species of plants and animals that are listed as either state or federally threatened or endangered are associated with California's grasslands (source).  

According to the 2019 report, Decline of the North American Avifauna, grassland birds have suffered a 53% decline in numbers since 1970.  So, since Kenn Kaufman hitchhiked across the continent on his legendary Big Year in 1973, more than half of North America's grassland birds have disappeared.  Drive the backroads across the prairies and grasslands of our country, and you will see less than half the number of grassland birds that were present 50 years ago.  Three out of four grassland species are in steep decline, including meadowlarks and Horned Larks. 

Savannah Sparrow

While almost all of the Great Central Valley's grasslands on the flat valley floor have long since been converted to agricultural land or paved over, the surrounding hills have historically been the strongholds of vast acreages of ancient grassland habitat.  But with the advent of drip irrigation technology, which allows previously flood-irrigated crops, like trees and vineyards, to receive water even on slopes, these strongholds have been breached and massive swaths of grassland are falling to deep-ripping and orchard conversion.  

The grasslands surrounding the Valley are being plowed up at an alarming rate, the soil ripped open and laid bare to become yet another monocrop of nut trees.  

Contrary to popular belief, California's grasslands are not just one successional stage on the way to becoming a climax community of orchards and vineyards!  

Lest I step on any toes, I ought to state right now that I am not entirely anti-agriculture.  I have a degree in agriculture, and I understand the utterly vital role ag plays in the economy of the Central Valley.  But I cannot see how planting more and more water-thirsty orchards and vineyards on previously unirrigated rangeland is a viable long-term solution in a region hard-pressed for water.  This form of agriculture simply cannot be supported indefinitely in our arid, drought-prone Mediterranean climate.

I can, however, see the benefit of sustainably grazing cattle on our grasslands.  

Grasslands, vernal pools and cattle on the prairie lands between the Stanislaus and Tuolumne Rivers.

Let's not kid ourselves: California's grasslands ceased to exist in their "pristine" pre-contact state a couple hundred years ago.  As soon as Spanish settlers and missionaries introduced cattle to the region, exotic annual grasses began taking over, rapidly supplanting native perennial bunchgrasses.  Shortly thereafter, the major grazers of this ecosystem were wiped out.  And grasslands must be grazed: proper grazing promotes healthy grassland ecosystems, and without their grazers, grasslands decrease in productivity and ultimately the ecosystem suffers.  

Without herds of pronghorn antelope, deer and elk to graze California's grasslands, sustainably managed herds of cattle are the next best thing.  Yes, overgrazing is always a risk, but this can pretty much entirely be mitigated against by taking care not to overstock the land and ensuring herds are regularly rotated through pastures, allowing grazed land time to recover.  

Check out this encouraging article to learn about how Audubon is working with cattle ranchers in the West to save grasslands and the birds that depend on them through the Conservation Ranching Initiative.

Cattle on grasslands north of Highway 4

Next time, we'll talk about two very special, very important grasslands along the eastern side of California's Great Central Valley.  Stay tuned!