These two pics aren't mine - they're my son's who photographed them in Death Valley and I just thought they were great and knew one of you could put a name to them.
Wow, those photos bring back memories... I love Death Valley N.P.. Such elegant bareness, like the backbone of the earth, exposed.
The second photo is a Joshua tree, Yucca brevifolia (or some closely aligned species). Fascinating to look at, in the same way that I could spend the whole day looking at saguaros - every one is different. Interesting in that their requirement for drainage restricts them to a certain zone on the bajadas (alluvial fans) that run off the mountain slopes. (The calves finding some shade(?) in that photo suggest that it is from outside the park proper, likely.)
I agree with Lori about Yucca brevifolium, however may I note that this is a very anomalous weeping form? It would be very interesting to try and root a cutting and see if it is environmental or genetic. It is really cool.
The cactus is Echinocereus coccineus (what used to be called Echinocereus triglochidiatus var. mojavensis) It grows from California all the way to Colorado, where it is quite abundant in the flats around Grand Junction. Despite its desert origins, it is very adaptable in our gardens, and bone hardy!
Death Valley is certainly a hot spot I have to visit! I remember reading "Westerns" in my youthhood (and a writer named Zane Grey if I am not mistaken).