Despite being 20 times smaller and having much lower rainfall, Richtersveld has more plant species than the country's famous Kruger national park. It is, says Van Wyk, "the most important succulent laboratory in the world". But it is this variety of rare succulents that draws the poachers. Many Richtersveld species are so specialised that they grow only in one valley or on one mountain slope. In extreme cases an entire species can be confined to an area smaller than a football pitch, so a poacher could render a species extinct in a morning. In Van Wyk’s estimation, plant poaching might be more lucrative than the country's rhino horn industry.