Question

Which plant is described by these clues? Its tiny five-petalled flowers sit in umbrellas of umbrellas: many stalks spring from a single point on the stem, and each one ends in a smaller umbrella of its own. Each dry fruit splits at maturity into two ribbed one-seeded halves about 0.1 inch (2.5 to 3 mm) long. Crush the foliage and it gives off a rank, musty, mouse-like smell, with nothing of the sweet kitchen aroma its relatives are grown for. Below ground it runs a single white fleshy unbranched {taproot}, not a cluster of swollen finger-like tubers. Every part carries the piperidine alkaloids coniine and gamma-coniceine, which paralyse the muscles of breathing; as little as 0.2 percent of body weight in fresh foliage kills cattle. Its second-year stems are hollow, smooth and completely hairless, and are streaked and blotched with purple to reddish-purple. In its first year it is only a flat {rosette} of glossy dark-green leaves cut three or four times over into fine fern-like segments, up to 20 inches (50 cm) long. By its second summer it stands 3 to 8 feet (90 to 240 cm) tall, overtopping almost everything it gets mistaken for. A single plant sets 35,000 to 40,000 seeds, and they stay viable in the soil for three to six years. The species epithet simply means spotted, for the purple markings on its stalks. This is the plant of the cup handed to Socrates after his trial in Athens in 399 BCE, and it now lines ditches, riverbanks and roadsides across most of North America.

Accepted Answer

Conium maculatum

Name That Plant #032