Monsonia patersonii stems

The spiny, hard stems of Monsonia patersonii, sometimes commonly known as hellthorn, are angled from nearly prostrate to erect; the plant in picture quite upstanding.

Persistent leaf petioles turned hard spine may be more prevalent on the stems than on the old plant shown here. The spines are often arranged in a few columns, vertically up the stems. Young spines may be red-brown, old dry ones whitish or grey. The spines are mostly straight, sometimes slightly curved down and sharply pointed.

Clusters of short spines are also present at the nodes of old bare stems next to the solitary long one. Monsonia leaves differ in two petiole length types. Both leave their petioles behind on the stems where they perform defensive services.

The smooth stem surfaces covered in a waxy bark are yellow-brown or olive-green to quite dark. These stems are highly flammable. A burning stem gives off an unpleasant odour reminding of incense. The thick-stemmed monsonias of the dry regions are generally known as bushman candles, associated with fire and light (Williamson, 2010; Manning, 2009; Le Roux, et al, 2005; iNaturalist).