For the pre-dawn departure on my morning cycling today I was rewarded with a splendid display of the spring blooms of the yucca brevifolia, a few examples of which have been planted in Scottsdale and Paradise Valley.
Most of the Joshua trees I have seen have been in the Mojave Desert of southeastern California (home of the magnificent Joshua Tree National Park), or along the Highway 93 route from southern Arizona to southern Nevada through the Joshua Forest Scenic Road.
Joshua trees can grow to 50 feet in height, at the excruciating rate of only 3 inches per year in their first 10 years, and only 1.5 inches per year thereafter. But they achieve their height with incredible longevity. The oldest can be 1000 years of age.
The flowers of the Joshua tree are proudly displayed on a spire that botanists call a “panicle,” the better to attract the co-evolved Yucca moth to pollinate and leave behind her eggs. The larvae will eat a few of the seeds.
Like the saguaro cactus of our Sonoran Desert, the signature flora of the Mojave doesn’t begin to branch for a long time. I believe I read that the first bloom occurs at about ten years of age, followed by the first branches.
So the Joshua tree in the first photo above is probably blooming for the first time ever. This larger cousin could be twenty or thirty years old…still a toddler in Joshua tree-years.