This section is from the book "An Illustrated Flora Of The Northern United States, Canada And The British Possessions Vol3", by Nathaniel Lord Britton, Addison Brown. Also available from Amazon: An Illustrated Flora of the Northern United States, Canada and the British Possessions. 3 Volume Set..
Erect, perennial or biennial, simple or branched, strict hispid or scabrous herbs, blackening in drying, the lower leaves opposite, the upper sometimes alternate. Flowers rather large, white, blue, or purple, in dense terminal bracted spikes, the lower commonly distant. Calyx tubular, or oblong, 5-10-nerved, 5-toothed. Corolla salverform, its tube cylindric, somewhat curved, its limb deeply and nearly equally 5-cleft, spreading, the lateral lobes exterior in the bud. Stamens 4, didynamous, included; anther-sacs confluent into I. Style slender, thickened or club-shaped above; stigma small, entire or emarginate. Capsule oblong or ovoid, loculicidally dehiscent. Seeds numerous, reticulated. [Named for J. G. Buchner.]
About 30 species, natives of warm and temperate regions. Besides the following, another occurs in the southern United States. Type species: Buchnera americana L.
Buchnera americana L. Sp. Pl. 630. 1753.
Hispid and rough; stem slender, stiff, 1°-2 1/2° high. Leaves usually all opposite, prominently veined, the lowest obovate or oblong, obtuse, narrowed into very short petioles, the middle ones oblong or oblong-lanceolate, dentate, obtuse, or acute at the apex, narrowed at the base, sessile, the upper lanceolate or linear-lanceolate, entire or nearly so; spike peduncled, 6'-10' long in fruit, the flowers mostly opposite, nearly 1' long; bractlets shorter than the calyx; calyx strigose; corolla purple, its lobes obovate, obtuse, 3"- 4" broad; capsule slightly oblique, 4" high, a little longer than the calyx.
In sandy or gravelly soil, New Jersey to western New York, southern Ontario and Minnesota, south to Virginia, Louisiana, Kansas and Arkansas. June-Sept.