The pale, thin bark of Aspalathus spinosa subsp. spinosa on the rigid, rod-like branches develops shallow fissures, revealing underbark that is similarly coloured and textured, not quite smooth.
The spines vary in length, rigid and often sharp-tipped. They are not smooth, showing bulges where leaf or flower had grown in the days when the bare spine had still been a contributing branchlet.
Leaves on the old stems in picture are mostly solitary, although still trifoliolate unless a leaflet has been lost (Curtis-Scott, et al, 2020; Vlok and Schutte-Vlok, 2015; Pooley, 1998; Bond and Goldblatt, 1984; iNaturalist; http://www.worldfloraonline.org).