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Key to Hieracium

Asteraceae

Hieracium

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1 Cypselas 1-2.5 mm long; pappus of 25-40+ white to sordid bristles, in 1 series; plants stoloniferous (cespitose in a few species); corollas yellow or orange
1 Cypselas (2-) 2.5-7 mm long; pappus of (30-) 40-80 white, tan, or sordid bristles, in 1-2+ series; plants cespitose; corollas yellow.
  2 Leaves primarily cauline, the largest leaves definitely on the stem, basal leaves usually absent.
    3 Florets 8-20 (-30) per head; leaves nearly glabrous, or with a few long hairs on the lower surface; upper stem glabrous
    3 Florets 30-110 per head; leaves setose, with long hairs on the upper and lower surfaces; upper stem stipitate-glandular, stellate-pubescent, or glabrous.
      4 Leaves with entire margins, rounded to obtuse at the tip; [widespread in our area]
      4 Leaves with toothed to laciniate margins, acute to obtuse at the tip
        5 Leaves 2-4× as long as wide; [exotic, mainly in disturbed situations]
        5 Leaves (3-) 5-10 (-15)× as long as wide; [disjunct at high elevations in WV]
  2 Leaves primarily basal, the largest leaves basal, leaves in some species extending onto the lower portion of the stem.
          6 Leaves purple-veined (when fresh).
             7 Lower stem strongly pilose; leaves weakly purple-veined
             7 Lower stem glabrous or nearly so; leaves strongly purple-veined
          6 Leaves not purple-veined.
                 9 Cypselas truncate, broadest at the tip; flowers 40-100 per head
                 9 Cypselas narrowed to the tip; flowers 20-40 per head
                   10 Hairs of the lower stem 1-4 mm long; inflorescence 2-4× as long as wide; [widespread in our area]
                   10 Hairs of the lower stem 6-15 mm long; inflorescence 4-7× as long as wide; [of KY and TN westward]
                       12 Leaf bases of basal leaf blades cuneate; reproductive stems with 2-10 leaves.
                          13 Cypselas 2-3.5 mm long, truncate, broadest at the tip or along the length; flowers 40-100 per head
                          13 Cypselas 2.2-5 mm long, at least the longer achenes narrowed to the tip; flowers 15-40 per head.
                            14 Stem with several well-developed leaves slightly smaller than the basal leaves; inflorescence corymbiform or tending toward paniculate.
                              15 Involucre mostly 6-9 mm high; inflorescence generally elongate and cylindric (appearing corymbiform in depauperate individuals); achenes 2.5-4 mm long; corollas 8-9 mm long
                            14 Stem leafless, or with only a few leaves distinctly smaller than the basal leaves; inflorescence strongly corymbiform.
                                  17 Involucral setae not gland-tipped (but with shorter gland-tipped hairs); [of the Mountains (and Piedmont?) of VA]