The clump of Orbea lutea subsp. lutea stems shown here show the flat, long, triangular tubercles or teeth of this plant. The stem surfaces are blue-green on the older ones, pale green where the summer rain has brought new growth. Irregularly shaped maroon blotches, spots and streaks are scattered all over the stems, except on top of every tooth where a white ridge is found.
More than halfway up each tooth two small lateral protuberances are visible, referred to by White and Sloane (1937) as “pellucid denticles”, which would mean translucent small teeth. The teeth become markedly narrower immediately up from these two small branches.