Historic Joshua Tree Bloom: What's the Cause?It’s bloom time for Joshua Trees, the spikey sentinels of the Mojave Desert that stretches across the southwest. This year’s prolific bloom is sending tourists out in droves to see the trees. But as Fronteras Desk reporter Jill Replogle reports, the phenomenon could be a sign of the trees’ precarious future.
JOSHUA TREE NATIONAL PARK — It’s bloom time for Joshua trees, the spikey sentinels of the Mojave Desert that stretches across the southwest.
They’re among the most bizarre-looking of desert flora. Though they’re technically trees, these spikey towers look more like a cross between a palm and a cactus.
Each spring, many Joshua trees send out large pineapple-shaped crowns of white-green flowers. This year, the blooms are especially large, and widespread.
“As far as we can tell, the entire range of Joshua trees is in bloom right now," said Pat Pilcher, an interpretive ranger at Joshua Tree National Park.
Biologists and ecologists don’t quite know what’s behind the high-volume bloom. Some think the trees are benefiting from just the right climate conditions.
But others say the trees seem to be desperate to reproduce — stressed by two years of unusually low rainfall.
“Sometimes plants will bloom when maybe it’s their last stages of life," said Pilcher. "They put out a tremendous amount of energy and say, 'well, this is it, I’m going to go out in style.'”
Joshua trees may be a harbinger — and a victim — of a warming planet. A 2011 study led by an ecologist at the U.S. Geological Survey predicted that rising temperatures could cause the trees to disappear from 90 percent of their range in as little as 60 years.
For now, tourists and nature lovers across the southwest are enjoying perhaps a once in a lifetime phenomenon.
“It’s neat with the trees and the formation of the rocks, and all of a sudden you see bright colored flowers popping out," said Dennis Haines from Pennsylvania, who was visiting the park for the first time. "I think it’s gorgeous, I can’t wait to bring my wife out here to see it.”
Joshua tree flowers only last a few weeks, and this year's blooms are fading fast.