Tree Believed To Be CA's Oldest Threatened By Housing Development

JURUPA VALLEY, CA — One of the oldest living organisms on Earth is located in Riverside County: a shrubby oak tree estimated to be about 13,000 years old that exists in the hills above Jurupa Valley.

Some worry the oak's life is now threatened by a large-scale development project planned for the area.

In 2009, researchers from two University of California campuses — Davis and Riverside — discovered Palmer's oak persisting in a spot overlooking what is now the city of Jurupa Valley. The oak is native to California and is not listed as endangered or threatened, but perhaps no other specimen is as special as the 4-foot-tall Quercus palmeri living in the hills above Jurupa Valley.

Palmer's oak usually grows in small populations, some of which are actually "clones" of a single plant. The Palmer's oak above Jurupa Valley — affectionately named the Jurupa Oak — is one such clone and the researchers believe it is at least 13,000 years old.

The oak is presumed to be a relic of a formerly larger range of the species that has largely disappeared over thousands of years in the area following the end of the Pleistocene epoch that spanned some 2.58 million to 11,700 years ago, according to the researchers, who summarized their findings in "A Pleistocene Clone of Palmer's Oak Persisting in Southern California."

"We propose that this stand of Q. palmeri is a relict of an ancient population that has persisted in the Jurupa Mountains despite warming since the last glacial period," the researchers wrote. "Our findings are not without precedent, as ancient clones have been identified in other woody taxa, including a nearly 12,000-year-old clone of creosote (Larrea tridentata Coville) found in the Mojave Desert. Nonetheless, our 13,000-year estimate for the age of the Jurupa clone places it among the oldest of living plants."

How the Jurupa Oak survived is unclear, but now it must contend with a proposed master planned community called Rio Vista, which calls for more than 1,500 new homes, commercial construction, elementary schools, parks, an equestrian center, and light industry in the area.

A Los Angeles Times article published this week highlights concern from researchers, native plant enthusiasts and tribal leaders over the Jurupa Oak's fate.

“From the beginning, we’ve been opposed to this development,” said Matthew Teutimez, a tribal biologist. “It’s not just the oak — we’re concerned about that whole landscape of hill complexes that have been used for ceremonial purposes for thousands of years.”

While the development calls for measures to protect the Jurupa Oak, critics say those efforts don’t go far enough. A coalition of environmental groups is seeking buffer zones of 1,500 feet or more around the Jurupa Oak and the organizations would like to see a scaled-down version of the proposed development, the Los Angeles Times reports.

Nick Jensen, conservation program director for the California Native Plant Society, told the newspaper, "The proposed development would introduce a potentially catastrophic mix of wildfires, trampling, pollution, pathogens and invasions of exotic plants and animals."

Read the full Los Angeles Times story here.