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Key to Monarda

Lamiaceae

Monarda

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1 Flowers in a single, terminal glomerule (rarely also 1 at the next node down the stem); stamens exserted; leaves ovate to ovate-lanceolate, broadest near the rounded, truncate, or subcordate base, 1.5-3 (-4)× as long as wide.
  2 Leaves all sessile, or the best-developed with petioles < 5 mm long.
    3 Upper corolla lip about ½ as long as the corolla tube
  2 Leaves petiolate, the well-developed leaves with petioles (5-) 10-40 mm long.
      4 Corolla 30-45 mm long, scarlet-red, (3-) 4-8 mm broad at the expanded portion of the throat; [primarily of mountain seepages, streambanks, and boggy places]
      4 Corolla 14-35 (-36) mm long, white, lavender, or purple, 1-3 (-4) mm broad at the expanded portion of the throat; [of various habitats, usually dryish to mesic].
        5 Leaves deltoid-ovate to ovate, 2-6 cm wide, usually ca. 2× as long as wide; orifice of the calyx glabrous to slightly hirsute with a few long hairs; upper lip of the corolla 5-8 mm long and not bearded (M. clinopodia) or 13-16 mm long and slightly bearded (M. media) near its apex; outer surface of the corolla glabrous to evenly pubescent with short curled hairs.
          6 Corolla white, greenish, or pale pink, the lower lip purple-spotted; outer bracts subtending the inflorescence green or pale (rarely with a purplish midvein); upper lip of the corolla 5-8 mm long, not bearded
          6 Corolla deep purple, the lower lip usually not spotted; outer bracts subtending the inflorescence purple to red; upper lip of the corolla 13-16 mm long and slightly bearded near its apex
        5 Leaves narrowly-deltoid, ovate-lanceolate to lanceolate, 1-4 cm wide, usually ca. 3-4× as long as wide; orifice of the calyx densely hirsute with numerous erect, stiff, white hairs; upper lip of the corolla prominently bearded or merely pilose near its apex; outer surface of the corolla evenly pubescent with short curled hairs.
             7 Corolla pink to lavender, or white to cream, or creamy yellow; upper corolla lip with a tuft of distinctly longer trichomes at the apex, or trichomes dense and of the same length throughout; leaves generally gray-green due to dense canescent trichomes on both surfaces, or greenish and densely hirsute.
               8 Plants 50-150 cm tall; flowering late spring and into summer (Jun-Aug); corollas pink to lavender (rarely white).
                 9 Pubescence of the petioles and lower leaf surface hirsute and/or villous, the trichomes spreading, 1-3 mm long
                 9 Pubescence of the petioles and lower leaf surface canescent, the trichomes appressed (sometimes also with an admixture of longer, spreading trichomes)
               8 Plants 20–50 cm tall; flowering in spring (April–early June); corollas white, creamy white, to yellow, rarely pink to lavender.
                   10 Glomerules loose with obvious branches; calyx typically densely shortly hirsute throughout and eglandular or with a few scattered stipitate glandular trichomes
                   10 Glomerules not loose, branches not apparent; calyx with trichomes on the veins and glabrous to very sparingly pubescent between the veins, large prominent punctate glands on calyx, stipitate glandular trichomes on veins.
                     11 Lower stem pubescent like the upper nodes and hirsute to hispid pubescent; lamina surfaces hispid-hirsute; corolla creamy white to creamy yellow, upper corolla apex without a tuft of longer trichomes at apex
                     11 Lower stem typically shaggy pubescent with trichomes up to 1 cm long; lamina surfaces canescent; corollas typically white, creamy white, to yellowish tinted, occasionally pinkish, upper corolla apex with a tuft of longer trichomes.
             7 Corolla typically white to creamy-white, yellowish, greenish, or occasionally with some pink or lavender hue; upper corolla lip without a tuft of longer trichomes at the apex, trichomes sparse and the same length throughout; leaves generally green to dark green, typically glabrous with only marginal cilia or scattered pubescence on abaxial veins, rarely adaxially on veins.
                       12 Margins of leaves with short trichomes or glabrous, 0.1-0.4 mm long, appressed; stems with 1-2 mm long trichomes on angles and at nodes proximally, internodes subtending glomerules with short curled trichomes on faces and angles
                       12 Margins of leaves with long ciliate trichomes, 0.75-2 mm long, spreading or shorter trichomes appressed; stems glabrous or variously with trichomes on angles and/or faces, nodes densely bearded, internodes subtending glomerules with various pubescence.
                          13 Stem faces and angles glabrous to glabrate with only a few scattered trichomes below uppermost nodes; petioles glabrous or with minimal short trichomes; leaves glabrous except for marginal short trichomes; calyx 9-12 mm long, densely stipitate glandular pubescent, calyx lobes 1-1.5 mm long
                          13 Stems glabrous on faces, angles with scattered longer trichomes, or glabrous above midstem; petioles with long spreading trichomes; leaves sometimes pubescent abaxially, and with marginal long or short trichomes; calyx 6-11 mm, pubescent with some stipitate glandular trichomes, calyx lobes 0.75-1.6 mm long.
                            14 Leaves adaxially lustrous, abaxially glabrous except midvein with a few scattered trichomes, marginal serrations 0.5-1 mm deep, marginal cilia 0.5-1.5 mm long; calyx 6-11.5 mm long, calyx lobes 1-1.6 mm long
                            14 Leaves adaxially matte, abaxially with long trichomes on veins, marginal serrations often conspicuous, 0.5-2 mm deep (especially in northern part of range), marginal cilia 0.5-1.1 mm long; calyx 7-9 mm long, calyx lobes 0.75-1.3 mm long
1 Flowers in 2-6 glomerules, terminal and at 2-5 successive nodes down the stem from the terminal glomerule; stamens included; leaves linear, lanceolate, to narrowly elliptic, usually broadest near the middle and tapered to a cuneate base, (2.5-) 3-8× (or more) as long as wide.
                              15 Calyx lobes (3-) 5-10× as long as wide, the length including a spinose awn 2-7 mm long; corolla white to pink or lavender; inner bracts subtending the flowers 4-9 mm wide, abruptly acuminate into a spinose bristle
                                16 Bracts subtending the glomerules of flowers similar in shape, the outer bracts and inner bracts not strongly differentiated in width; corolla white to pink or lavender, with purple spots
                                16 Bracts subtending the glomerules of flowers graduated in shape, the outer 2× or more as wide as the inner; corolla white to pink or lavender, usually without purple spots.
                                    18 Calyx tips stiff, 3-6 mm long, reddish or purplish; bracts elliptic, with veins strongly raised
                                    18 Calyx tips flexible, 1-3 mm long, greenish; bracts ovate, with veins only slightly raised
                              15 Calyx lobes 1-3× as long as wide, narrowly to broadly triangular, acute or long-acuminate but not awned; corolla yellow, spotted with purple; inner bracts 8-14 mm wide, acuminate.
                                         20 Shrub, strongly and diffusely branched; leaves linear, ≤ 3 mm wide; stems and leaves canescent; petiole absent or minute, < 1 mm long
                                               23 Calyx teeth narrowly acute; calyx tube with scattered hairs between (and on) the veins; flowers yellow.
                                                    25 Leaves 2.2-3.5 cm long; upper bract tip acute; calyx lobe tips acuminate; [Atlantic Coastal Plain of ne. SC south to peninsular FL]