Wild Coffee
or Feverwort
Triosteum perfoliatum
From Missouri Plants
Stems - Single or multiple from the base, erect, herbaceous, fistulose, to 1m tall, simple, with short glandular pubescence and longer non-glandular hairs.
Leaves - Opposite, sessile to perfoliate (the lower and middle leaves perfoliate). Blades widest near the apex, acuminate, entire, dull green above, lighter green abaxially, densely short-pubescent abaxially, less pubescent adaxially, to +20cm long, +8cm broad. Veins expressed abaxially.
Inflorescence - 1-6 sessile flowers in the leaf axils.
Flowers - Corolla yellowish to reddish-purple, tubular, glandular pubescent externally, mostly glabrous internally, -2cm long, 5-lobed, gibbous at the base with a small reservoir for collecting nectar. Lobes rounded at the apex, 5-6mm long, 5mm broad. Stamens 5, alternating with the corolla lobes, attached along the entire length on the corolla tube, included. Filaments free for half their length (+/-5mm), pubescent, yellow. Anthers yellow, 4-5mm long. Style exserted, to 2cm long, pubescent, whitish to pale yellow. Stigma capitate, 4-lobed, 2-3mm broad. Ovary inferior, 3-4-locular, 3-4-seeded(?). Calyx lobes 5, spreading, linear, glandular and simple pubescent, typically reddish, accrescent, +/-1.5cm long, +/-2mm broad in flower. Calyx tube green, subglobose, densely glandular and simple pubescent, 3mm in diameter in flower, accrescent.
Flowering - May - July.
Habitat - Dry open woods and thickets.
Origin - Native to U.S.