These plants look like they belong on a different planet. They are a type of groundsels.
Dendrosenecio kilimanjari is a giant groundsel found atop Mount Kilimanjaro in Africa. It was originally known as Senecio kilimanjari, but a recent botanical reclassification split off some species formerly in Senecio, putting it and various other species in the new genus Dendrosenecio. Both genera are in the family Asteraceae. The giant groundsels of the genus Dendrosenecio evolved, about a million years ago, from a Senecio that established itself on Mount Kilimanjaro, with those that survived adapting into Dendrosenecio kilimanjari. This later colonised other mountains by some means – the standard distance for wind dispersal of seeds is a few metres – and these isolated populations adapted in ways different from the parent population, creating new species.