"We're not going to let this tree die," said Georgios Vidalakis, UC Cooperative Extension specialist in the Department of Plant Pathology at UC Riverside. Vidalakis is the director of the UC Citrus Clonal Protection Program.
Scientists protect the tree using special tools, insecticides and disease monitoring.
According to legend, the seedless and sweet Washington navel was an accidental mutant that appeared on the grounds of a Brazil monastery in the early 1800s. Tree clones were sent to USDA in Washington, D.C., and from there acquired by Eliza Tibbets, who tended the trees at her home in Riverside.
"Producing budding stock to make other saplings, Tibbets' trees birthed a citrus industry dubbed California's second gold rush," the Press-Enterprise story said.
John Bash, a UC Riverside staff researcher who worked with the Washington navel for 32 years, called the mother tree "one of the world's agricultural icons."
"There are literally millions and millions of trees that can trace their ancestry back to that single tree," Bash said.