Monthly Archives: January 2019

Roldana cristobalensis (formerly Senecio cristobalensis…now, Roldana petasitis var. cristobalensis)

Roldana petasitis var. cristobalensis shown here looking amazing with Aeonium arboretum ‘Zwartzkop’.  Its substantial leaves are some 8″ across, thick and velvety, the undersides of which are red/purple, like the stems.  The color often comes through in the veins along the top surface.  A very striking foliage plant.  Picture this with its close relative, Pseudogynoxus chenipodiodes, the Mexican Flame Vine, formerly known as Senecio confusus!

Sometimes called Velvet Groundsel, this plant has been living and marketed under several different names.  The first name in the heading is the one Jimi Blake ascribed to it, a name I didn’t recognize for a plant I’ve grown off and on in the past…it got lost in his list paired with a particular Thalictrum and I simply missed it…until recently.  I knew it as Senecio cristobalensis and, had I recognized it, would have included it with an earlier post in which I focused on his favorite Asteraceae.  I did actually mention the plant there simply as another Senecio that I’ve grown of value.  Here I shall treat it more directly.  The genus, Roldana, was recircumscribed in 2008 to include some 54 different species.  Other authors include as few as 48 and as many as 64 in the genus, most of which used to belong to Senecio and are native to the extreme Southwestern US, Mexico and Central America.  Most of the Roldana species are somewhat ‘shrubby’ herbs with a few, like this one woody, even tree like.  Both genera are within the Asteraceae and share tribe status as well, Senecioneae.  For the curious, Roldana spp., even more finely, are included in the sub-tribe, Tussilagininae, which includes the very commonly grown genus of garden plants…Ligularia!  On closer examination the morphological similarities will begin to stand out to most of us.  Check out all of the photos on the Wikimedia Commons page for Roldana petasitis.  Roldana petasitis is the correct species name for this plant.  With all of the shuffling and consequent confusion still going on in the world of taxonomy, especially in such a mixed large genera like Senecio, we must all be allowed our mistakes of nomenclature.  It is a volatile changing world out there. Continue reading

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