Question

Which plant is described by these clues? Its genus name is usually traced to the Latin verb meaning to wash, a nod to the Roman habit of scenting bath water and freshly laundered linen with it. Roll a flowering stem between finger and thumb and it is square in cross-section, and the leaves come off in opposite {decussate} pairs, each pair set at right angles to the pair below. Every flower leaves behind an {ovary} split so deeply into four that the single {gynobasic} style rises from the base between the lobes, ripening into four dry one-seeded {nutlets} rather than a capsule or a berry. Four short {didynamous} {stamens} stay hidden inside the two-lipped {corolla} so nothing protrudes at the mouth of the flower, and the topmost tooth of the ribbed {calyx} is widened into a small flat flap. Its epithet is simply a description of the foliage, narrow-leaved, and the grey-green blades run up to 2.5 inches (6 cm) long but barely 1/4 inch (4 to 6 mm) across, with {revolute} margins rolled under. In the wild it belongs to dry stony limestone slopes and {garrigue} in the mountains of Spain, southern France and Italy, roughly 2,000 to 6,000 feet (600 to 1,800 m) up. Its scent sits in glandular {trichomes} on leaf and {calyx}, and the distilled oil runs high in linalool and linalyl acetate while staying comparatively low in camphor, which is why the trade rates it the sweet, soft-smelling grade. Each wiry leafless stalk carries one unbranched violet {spike} 2 to 4 inches (5 to 10 cm) long that simply ends in flowers, with no crown of long coloured sterile {bracts} waving above the tip. Its dried flowers season herbes de Provence and shortbread and scent linen against clothes moths, and a standardised capsule of its flower oil has been tested against both placebo and lorazepam in randomised trials for generalised anxiety. The common name most gardeners use credits a cool, damp northern country where the plant has never grown wild; the label records where it was long cultivated and distilled, not where it comes from. Crossed with its broad-leaved, camphor-rich mountain cousin it produces the sterile hybrid that now fills most of the commercial oil fields of Provence, while the species itself is still sold under two superseded names meaning of the apothecary shop and the true one.

Accepted Answer

Lavandula angustifolia

Name That Plant #033