Question

Which plant is described by these clues? Its genus name travelled from a Semitic word for the bitter, glossy drug dried from its juice into Greek and then into botanical Latin, so the plant is named for a purgative rather than for anything soothing. Its blooms hang in a dense unbranched column on a bare stalk, each built of six segments joined for about half their length into a tube, with six {stamens} inside and a three-chambered {ovary} standing free above the base of the {perianth}. Cut across the leaf base and a bitter yellow juice beads from a ring of fine tubules lying just inside the rind, drying to a brown resin whose {anthraquinone} pigments scour the gut. Its thick, water-swollen leaves stand in a spiral {rosette}, every margin lined with firm pale triangular teeth set about half an inch (1 to 1.5 cm) apart. The best current evidence puts its wild home in the dry mountains of the southern Arabian Peninsula, in Oman and neighbouring Yemen, while the Mediterranean and Caribbean stands so often called native are escapes from ancient cultivation. Its epithet is simply the Latin adjective for true, staked in the drug trade to mark it as the genuine article among a crowd of bitter rivals, and it has nothing whatever to do with the colour green. It stays trunkless and knee-high, 12 to 24 inches (30 to 60 cm) tall, and widens each season into a colony by pushing up a ring of rooted {offsets} around its base. Its flowering stalk rises to about 3 feet (90 cm) and opens a plain soft yellow, where most of its close relatives flower scarlet or coral. Every other member of its genus needs paperwork to cross an international border under the wildlife trade convention, while this one is written into the treaty as an explicit exemption. The bitter yellow layer under its rind was sold for centuries as a laxative until American regulators pulled it from over-the-counter shelves in 2002 for want of safety data, while the clear jelly beside it went on into burn creams. It sits on kitchen windowsills the world over so a leaf can be snapped over a scald for its clear {mucilage}, which also thickens sunburn gels and floats as chewy cubes in bottled drinks, and gardeners forever confuse its rosette with the fibrous, spine-tipped century plant of an entirely different family.

Accepted Answer

Aloe vera

Name That Plant #117