If you want to see the oldest navel orange--the original 'Washington' navel that began the citrus boom in California--it survives on a tiny triangular plot wedged between Magnolia and Arlington avenues in Riverside, where it still produces fruit.
Labeled as State Historical Landmark 20, it was according to the plaque, planted in 1873 by Eliza Tibbets from a Brazilian seedling. If the plaque is correct, the tree is now 125 years old but is still surprisingly small.
One reference says that, by 1895, 20,000 acres of navel oranges grew around Riverside, all grown from the original tree's bud wood. The rest is history.
To see the latest in citrus, visit the California Rare Fruit Growers' Web site at http://crfg.org. Farm advisor and citrus specialist Ben Farber says it's packed with cultural and other information on citrus and all sorts of other subtropical fruit.