Hoodia pilifera subsp. pilifera stems

Many columns of small tubercular protuberances with tiny spine-tips form a dense, somewhat irregular pattern on the stem surfaces of Hoodia pilifera subsp. pilifera. In the rainy season, more winter than summer in the plant’s habitat, these stems that branch at the base assume a greener colour (Vlok and Schutte-Vlok, 2010; iSpot; www.cactus-art.biz).