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..
Perennial or annual erect aromatic herbs, with dentate or serrate leaves, and rather large white red purple yellowish or mottled flowers, in dense capitate clusters, mostly bracteate and bracteolate, terminal and sometimes also axillary, the bracts sometimes brightly colored. Calyx tubular, narrow, 15-nerved, nearly or quite equally 5-toothed, mostly villous in the throat. Corolla glabrous within, usually puberulent or glandular without, the tube slightly dilated above, the limb 2- lipped; upper lip erect or arched, emarginate or entire; lower lip spreading, 3-lobed, the middle lobe larger or longer than the others. Anther-bearing stamens 2, ascending, usually exserted, the posterior pair (staminodia) rudimentary or wanting; anthers linear, versatile, 2-celled, the sacs divaricate, more or less confluent at the base. Ovary deeply 4-parted; style 2-cleft at the apex; nutlets ovoid, smooth. [In honor of Nicolas Monardes, a Spanish physician and botanist of the sixteenth century.]
About 12 species, natives of North America and Mexico. Type species: Monarda fistulosa L. Flower-clusters solitary, terminal (rarely also in the uppermost axils); stamens exserted. Leaves manifestly petioled, the petioles commonly slender. Corolla scarlet, 1 1/2'-2' long; bracts red.
1. M. didyma.
Corolla white, pink, or purple, 1' -1 1/2' long.
Leaves membranous; corolla slightly pubescent, 10"-l2" long.
2. M. clinopodia.
Leaves thin or firm; corolla pubescent, 1' - 1 1/2' long. Pubescence spreading; leaves thin.
Corolla cream-color, pink, or purplish.
3. M. fistulosa.
Corolla or bracts deep purple or purple-red.
4. M. media.
Pubescence short, canescent: leaves firm, pale.
5. M. mollis.
Leaves sessile, or very short-petioled.
6. M. Bradburiana.
Flower-clusters both axillary and terminal; stamens not exserted. Calyx-teeth triangular; corolla yellowish, mottled.
7. M. punctata.
Calyx-teeth subulate-aristate; corolla white or purple, not mottled. Bracts lanceolate, gradually acuminate.
8. M. pectinata.
Bracts oblong to oval, not acuminate.
9. M. dispersa.
Monarda didyma L. Sp. Pl. 22. 1753.
Perennial; stem stout, villous-pubescent, or glabrate, 2°-3° high. Leaves thin, ovate or ovate-lanceolate, petioled, dark green, usually pubescent beneath, hairy above, acuminate at apex, rounded or narrowed at the base, sharply serrate, 3'-6' long, 1'-3' wide; lower petioles often 1' long; flower-clusters almost always solitary, terminal; bracts commonly red; calyx glabrous without, glabrous or slightly hirsute in the throat, its teeth subulate, nearly erect, about as long as the diameter of the tube; corolla scarlet, 11/2'-2' long, puberulent; stamens exserted.
In moist soil, especially along streams, Quebec to Ontario and Michigan, south to Georgia and Tennessee. Ascends to 5200 ft. in North Carolina. Red, low or fragrant balm. Horse- or mountain-mint. In-dian's-plume. July-Sept.