Mike and I have really wanted to explore Joshua Tree National Park and check it of off our National Park List.
The Joshua Tree is actually a yucca plant and is in the the same subgroup that includes flowering grasses and orchids. It grows primarily in the Mohave Desert, in elevations from about 1,300 to 5,900 feet above sea level.
Mormon pioneers encountered the species in the mid-1800s and named it after the Biblical story of Joshua. They saw the outstretched arms of the tree as a vision of supplication, guiding the westward bound pioneers, just as biblical Joshua helped lead the exploration of Canaan.
Most of the first European settlers, however, saw the desert as a wasteland. Others, like Minerva Hoyt, a Pasadena resident who was extremely fond of desert plants, became concerned about the removal of cacti and other plants to the gardens of Los Angeles. Her tireless efforts to protect this area culminated in 825,000 acres being set aside as Joshua Tree National Monument in 1936.
Joshua Tree National Park covers 1,235 square miles and is the second largest National Park in California, after Death Valley. What we as visitors see is only about 15% of the park area. The remaining 85% is managed as wilderness.
Geologists believe the face of our modern landscape was born more than 100 million years ago.
The Rock Pile formations are so cool!
Molten liquid, heated by the continuous movement of Earth’s crust, oozed upward and cooled while still below the surface. These plutonic intrusions are a granitic rock called monzogranite.
The monzogranite developed a system of rectangular blocks like those seen at Jumbo Rocks. As ground water percolated down through the monzogranite’s block fractures, it began to transform some hard mineral grains along its path into soft clay, while it loosened and freed grains resistant to solution. Rectangular stones slowly weathered to spheres of hard rock surrounded by soft clay containing loose mineral grains. Imagine holding an ice cube under the faucet. The cube rounds away at the corners first, because that is the part most exposed to the force of the water. A similar thing happened here but over millions of years, on a grand scale, and during a much wetter climate.
After the arrival of the arid climate of recent times, flash floods began washing away the protective ground surface. As they were exposed, the huge eroded boulders settled one on top of another.
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