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Key to Asteraceae, Key N: Herbaceous composites with the leaves alternate or basal and the heads radiate, the rays white, pink, purple, and the pappus absent or essentially so

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1 Receptacles paleate (with chaff); [tribe Heliantheae].
  2 Stems not winged; leaves simple; disc florets and ray florets differing in color
  2 Stems usually winged; leaves simple or pinnately to palmately lobed; disc florets concolorous (of similar color) with ray florets
1 Receptacles epaleate (lacking chaff).
      4 Plants arachnose or wooly pubescent throughout; [waif, SC; tribe Arctotideae]
      4 Plants glabrous or densely viscid but not wooly tomentose throughout (if hirsuto-pilose, this usually concentrated distally).
        5 Receptacles flat or broadly conic, not conspicuously pitted; heads in corymbiform arrays; pappus a short crown; rays white, pink, or purple adaxially; [widespread non-natives, tribe Anthemideae]
        5 Receptacles conic, pitted; heads borne singly (Aphanostephus) or in loose corymbiform arrays (Egletes); rays white adaxially; [natives primarily w. of MS river; tribe Astereae].
          6 Plants aromatic, but not densely viscid, instead sometimes hairy distally; ray laminae not shorter than involucre; phyllary margins broadly scarious; pappus coroniform or a mix of variously shaped scales; [widespread w. of MS river]
          6 Plants densely viscid with stipitate-glandular trichomes; ray laminae sometimes shorter than involucre; phyllary margins scarious or not; pappus of uneven rings; [TX]
    3 Leaves entire or toothed, but neither deeply lobed nor pinnatifid.
             7 Plants 1-3 cm tall, densely pin-cushioned (pulvinate); flowering heads sessile, borne singly, conspicuously nestled within the rosette leaves and proportionately of similar size; pappus persistent, of 12-35+ setiform scales in 1 series; phyllaries in 4-6+ series
             7 Plants of various size, but not densely pin-cushioned; flowering heads borne on stems, if peduncles short the heads not conspicuously nestled within similar-sized leaf rosettes; pappus various, phyllaries in 2-6 series.
               8 Pappus of 5-40+ longer inner bristles plus shorter outer scales or setae (these sometimes falling); stems and leaves often (but not always) stipitate-glandular.
                 9 Inner barbellate bristles numerous (5-40+); stems and leaves usually glandular; plants tap-rooted, fibrous-rooted, or stoloniferous; annuals, biennials, or perennials
                 9 Inner bristles barbellate or thicker, fewer (ca. 5); stems and leaves glandular (C. asteroides) or eglandular (C. asteroides; C. belliloides); plants tap-rooted annuals
               8 Pappus primarily of awns, scales, crowns, or thickened rings (these minute, 0.1-0.8 mm long), sometimes also accompanied by shorter inner scales or bristles; stems and leaves eglandular (sometimes minutely glandular in Chaetopappa bellidifolia).
                     11 Receptacles obscurely pitted; pappus of 2-3 sclerified awns plus often with 7-12 shorter bristles or scales; [collectively widespread]
                     11 Receptacles smooth; pappus of 2 thin awns plus an elliptic ring of shorter awns; [s. TX]
                   10 Cypsela margins not narrowly winged (4-angled in Aphanostephus but lacking marginal wings).
                       12 Receptacles conic, pitted; cypselae 4-angled; pappus of setiform to awn-tipped scales or short ciliate crowns (0.1-0.2 mm long, minute, thus requiring magnification)
                       12 Receptacles flat or slightly convex, smooth (not pitted); cypselae variously shaped but not conspicuously 4-angled; pappus of minute, thickened rings (C. bellidifolia) or erose cuplike crowns (C. imberbis)

Key to Asteraceae, old Key J: Herbaceous composites with the leaves alternate or basal and the heads radiate, the rays white, pink, purple

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1 Receptacles chaffy (paleate).
  2 Phyllaries dry, scarious-margined.
    3 Ray florets 1-5 mm long; heads small in corymbiform arrays
    3 Ray florets > 5 mm long; heads large, terminating the branches
      4 Ray florets < 2.5 mm long; disk florets sterile, with an undivided style
      4 Ray florets > 5 mm long; disk florets fertile, with a divided style.
        5 Ray florets pink or light purple, > 15 mm long; heads single
        5 Ray florets white, 5-10 mm long; heads 20-100 in a compound corymb
1 Receptacles naked (epaleate).
             7 Achene faces minutely glandular-glochidiate (bearing small gland-like bristles)
               8 Leaves basal; cypselae marginally 2-ribbed; mature plants < 2 dm tall
               8 Leaves cauline (and sometimes also basal); cypselae with ± 10 ribs; mature plants > 2 dm tall
          6 Pappus present, of bristles or scales.
                   10 Heads primarily discoid with reduced ray florets
                   10 Heads radiate with conspicuous ray florets.
                     11 Taprooted annuals; ray florets 1-7 mm long.
                       12 Leaves and stems not fleshy, rarely glabrous; cypselas < 1.4 mm long
                       12 Leaves and stems fleshy, mostly glabrous; cypselas > 1.4 mm long
                     11 Not taprooted and mostly perennials; ray florets > 3 mm long.
                          13 Ray florets usually > 60; blooming Apr-Oct
                          13 Ray florets usually < 60; blooming late May-Nov.
                            14 Receptacles hemispheric to conic; pappus often with 2-4 awns (Boltonia) or lacking awns and coroniform (Astranthium).
                              15 Achenes not narrowly winged, the surfaces minutely glandular-glochidiate (bearing small gland-like bristles)
                            14 Receptacles flat to slightly convex; pappus lacking awns.
                                           21 Pappus double, with inner bristles distinctly longer than outer bristles.
                                               23 Ray florets white to pink or blue or purple, more numerous (usually 8-30); cypselas glabrous to pubescent but not densely silky.
                                                 24 Ray florets white or pink to blue or purple; involucres 7-12 mm long; phyllaries usually > 1 mm wide.
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