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Fan Palm Oasis

There are only 158 desert fan palm oases in North America. Five are located in Joshua Tree National Park. Such oases typically occur along fault lines, where uplifted layers of impermeable rock enable underground water to reach the surface.The desert fan palm, Washingtonia filifera, is native to the low hot deserts of southern California where it can live for 80 to 90 years. Towering up to 75 feet, the desert fan palm is among the tallest of North American palms. It is definitely the heaviest; a mature desert fan palm can weigh as much as three tons. Its distinctive leaves are shaped like a fan and folded like an accordion. They measure up to six feet in length and are nearly as wide. Looking much like "petticoats," the fan palm’s dead leaves remain attached to its trunk until removed by fire, wind, or flood. Desert fan palms suck up water using a mass of pencil-wide rootlets so dense that the roots of other plant species cannot penetrate. This mass may extend as far as 20 feet from the trunk in all directions.

Lost Palms Oasis, Joshua Tree National Park