Euphorbia rhombifolia stems

Euphorbia rhombifolia plants branch much, starting from the base. The lax branches grow opposite each other or appear equal (dichotomous) when they fork at a stem-tip. Branching is decussate, i.e. a branching is perpendicular to the previous and following one. 

The stems lack spines and nearly always the diamond-shaped leaves mentioned in the specific name. The cylindrical, smooth stems are blue-green or blue-grey, yellow-green and sometimes reddish or purplish in colour, depending on treatment of the plant by the weather. Upper stems may be 8 mm in diameter (Williamson, 2010; Shearing and Van Heerden, 2008; Van Wyk and Gericke, 2000; Gledhill, 1981; iNaturalist).