Returning a Verdant Land to Its Roots

In 1983, a conservation group paid $1 million for a small plot of San Joaquin Valley oak forest and prairie just east of Visalia. It was the kind of deal that raised eyebrows, because no one at the time sank that kind of money into valley land unless the intent was to farm, graze, drill or subdivide it.

But there was something special about this place. In a region spanning millions of acres, the 324-acre plot was one of the last, best examples of how the San Joaquin Valley once looked.

“When you talk about preserving open space, a lot of people in the valley just sort of roll their eyes,” said Scott Spear, president of the Sierra Los Tulares Land Trust, the nonprofit group that runs the preserve. “But protecting open space is not the same as protecting a native landscape.”

After the land was acquired, trails were cut and signs posted inviting hikers to visit. With dogeared field guides and clipboards, volunteers combed the newly dubbed Kaweah Oaks Preserve, cataloging every plant, animal and insect they could find, and trying to figure out which species should be there but weren’t.

“We know so little about what these valley environments were like because they were hit hard so early,” said Kevin Rice, an ecologist at UC Davis. “That’s what makes it so hard to re-create. We know the species that were there, but we don’t know the structure--the relationship between those species--because there just aren’t many remnant sites.”

Although researchers believe less than 5% of the native landscape is left, most also agree the San Joaquin Valley was once one of the continent’s richest and most diverse ecosystems. Tens of thousands of tule elk and antelope grazed expansive grasslands, and tens of millions of waterfowl visited vast lakes and wetlands. Grizzly bears prowled oak forests that surrounded the rivers, feasting on acorns and berries.

It began to disappear with the arrival of Spanish missionaries in the 1770s. Domestic livestock brought weeds that corrupted native grasslands, turning them into fields of exotics. Later, a maze of irrigation ditches and aqueducts reworked the valley’s natural plumbing for the benefit of agriculture. The land was leveled, the oaks cleared. By the time the word “ecology” was coined in the 1930s, the valley’s landscape had been transformed.

Somehow, the land that was to become the Kaweah Oaks Preserve survived. The longtime owners never planted on the land because it flooded frequently until the Kaweah River was dammed in 1962. But cattle had the run of the place for decades and had nearly munched many native plants out of existence.

A simple, fateful decision was made by preserve volunteers. Other than pulling a few weeds, the preserve would be left alone. A few cows would be allowed to graze in the meadow, but they would be removed from the woods. And that was all it took, said Rob Hansen, a biologist and vice president of the land trust who in the past 18 years has watched the preserve spring back to life.

Walking through the preserve on a recent afternoon, Hansen ticked off a long list of native species, many of which could barely be found in 1983. There’s the California blackberry. Its small thorns couldn’t stop cattle from eating it. But cows wouldn’t touch the Himalayan blackberry, an exotic shrub with huge thorns that settlers planted in 1909. Without constantly being pruned by cows, the California blackberry has reasserted itself and taken back some ground from its exotic competitor.

Hansen pointed out sedges that some Native Americans still use to make traditional baskets, and spoke of the huge crop of wild grapes draping the oaks.

“The vines eventually kill the trees, but we don’t do anything,” Hansen said. “They produce a huge amount of food for wildlife.”

He zeroed in on two chirps coming from opposite sides of a field. Two male oak titmice were marking their territory. “We’ve counted 130 different species of birds in here, and I can hear five of them right now.”

Hansen pointed out mice burrows, a fungus called turkey tail and shrubs where the endangered valley elderberry beetle lives. And he named a long list of species that will never come back, including the grizzly bear. He talked about the surprisingly lush stand of trees, mostly valley oaks, which live only in California and are the largest of the oak species in North America.

Thick groves of oaks once covered 400 square miles of the valley floor. “The trees here aren’t the monsters,” Hansen said. “They’d be bigger, but streams aren’t flowing here where they used to, and they’re not flowing as long as they used to.”

Although amazed that such a wide variety of life exists on the preserve--perhaps three times the number of species found in an adjacent plum orchard--Hansen said there’s much more at stake than biodiversity.

“Part of finding out who you are is developing a sense of place,” he said. “A lot of kids who grow up here are ashamed of the valley. It’s not a ‘cool’ place like San Diego, L.A. and the Bay Area. But the kids don’t know what was here, what made it special.”

The late UC Berkeley geographer James Parsons made much the same point in a 1987 lecture. He said there are three ways of looking at the San Joaquin Valley. The first is to simply pass through it or ignore it. The second is to hold it up as an example of capitalism run rampant. Or, Parsons suggested, you can pull off the highway and decide to look at it.

Information and directions to the preserve are available at www.kaweahoaks.com.