I've hesitated to post this answer because of some inconsistencies with my interpretation of your photo, mainly the absence of leaves. But the more times I have revisited this question, the more convinced I am that these are very, dead Mojave Yucca plants (yucca schidigera). What happened to the leaves? Who knows.
These have possibly been dead for more than a decade, and may have been through a fire. Time & inferno dispensing with the remnants of the leaves and ash / burn marks, although in your photo significant degredation is visible at the bases of the plants which could be either rot or fire damage. See this photo, taken in Red Rock Canyon NV (circa 2014).
I cannot be certain, but I believe the yuccas in my included photo may be in the area burned in the 1992 Red Rock Proscribed burn.
All that said, fire would not be requisite for this type of preservation, the desert is hot and dry, organic material can persist for a very long time...
As for the one in your photo that is awkwardly curled over? Just the result of rot & time.