Question

Which plant is described by these clues? Its flower is one wide funnel of five petals fused edge to edge, the joins showing only as five faint pleats running from throat to rim. In bud that funnel is furled shut in a tight spiral, and it opens still creased along the twist. The fruit is a small dry {capsule} that splits to shed up to four hard angular seeds. Its {style} ends not in a single head-like knob but in two slender thread-like stigmas. The pair of small {bracts} sits well down the flower stalk, leaving the green {calyx} fully exposed rather than hooded over. The genus name is Latin for 'to twine around', for stems that sweep in slow circles as they grow until they meet something to wind up. Its blades are small arrowheads 0.5 to 2 inches (1 to 5 cm) long, each with two triangular lobes flaring outward at the base. The funnels are only 0.6 to 1 inch (1.5 to 2.5 cm) across, white to pink, often banded with five deeper pink rays, and faintly almond-scented. Its roots drive more than 20 feet (6 m) straight down and run up to 25 feet (7.5 m) sideways, and a fragment left in the soil rebuilds the entire plant. The epithet means 'of the ploughed field', which is exactly where it does its worst. Buried seed of this plant has been recovered and germinated after 60 years, which is why hoeing the top growth off a colony achieves almost nothing and why it was proclaimed the worst weed in California and much of the western United States by the 1920s.

Accepted Answer

Convolvulus arvensis

Name That Plant #066