Cover Story: The graph shows how leaf succulents (succophylls) in the Namib Desert of South Africa store high levels of water at high levels of water potential (ψ) that changes little during the year. The non-succulents store much less water at lower ψ, both declining markedly during the dry season, indicating marked osmotic adjustment under drought stress but recovering quickly in the wet season (going from right to left). As extreme succophylls, the CAM species showed least rate of water loss when severed from the parent plant, transpired overnight, had the highest N/P contents per leaf area and greatest water use efficiency. View the paper.