Hoplophyllum spinosum stems look very much like the plant’s leaves, apart from having leaves emerging from them, thicker and ending in another leaf if not in some flowers.
The leaves in turn look very much like spines and surely function as such, although stock and game commonly browse this plant. The specific name, spinosum, is a Latin word meaning spiny or prickly, referring to the leaves resembling spines.
The narrow green and white stripes on stems and leaves are associated with fine grooves, the green continuous on the leaves, broken on the stem in picture. The leaves spiral in imprecise manner, i.e. at unequal angles around the stem, well-spaced although not equally spaced up it. Leaf-tips are brown and sharp, not to be ignored.
The photo adheres to a horizontal plane deviant from the flat ground where the plant grows, from the Maskam Mountains in the distance and from the angle of the branch, still telling a story from its perspective (Le Roux, et al, 2005; Leistner, (Ed.), 2000; iNaturalist; Wikipedia).