Those look a lot like creosote rings [1]. Creosote's native to southern Nevada and grows in clonal colonies that end up looking like rings, and that looks like

Those look a lot like creosote rings [1]. Creosote's native to southern Nevada and grows in clonal colonies that end up looking like rings, and that looks like a nice wide place where water would gather. [1] https://en.wikipedia.org/wiki/Larrea_tridentata https://en.wikipedia.org/wiki/Larrea_tridentata