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Taraxacum

Authorities disagree on how best to treat Taraxacum. Numerous microspecies have been distinguished, sometimes on very subtle distinctions. The species are treated here in the broad sense. Taraxacum ceratophorum (Ledeb.) DC. was reported from NH based on an immature specimen collected in Kings Ravine on Mount Adams, Coos County (Pease 1917). However, no mature specimens have ever been collected to verify the identity of the plant. Further, the specimen (at NEBC!) shows narrow and reflexed (in part) outer involucral bracts that are very unlike T. ceratophorum (i.e., the specimen appears misidentified and is likely T. officinale). Taraxacum ceratophorum has also been reported from MA and ME by Magee and Ahles (1999); however, this report was based on incorrectly synonymizing T. latilobum (specimens at NEBC!) with T. ceratorphorum (the two taxa are very distinct are do not comprise the same species). References: Fernald (1933), Brouillet (2006b).

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T. laevigatum
1a. Inner (i.e., longer) involucral bracts with a dark, corniculate appendage at the tip [Fig. 471]; cypsela body at maturity purple-red to brown-red; leaf blades lacerate-lobed with narrow lobes, the medial lateral lobes of leaf blades 1–10 (–12) mm wide at the base
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1b. Inner involucral bracts lacking dark, horn-like appendages at the tip; cypsela body at maturity light brown to gray-brown to brown; leaf blades toothed to lobed, the medial lateral lobes of leaf blades, when present, (5–) 10–32 (–38) mm wide
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  T. palustre
  2a. Outer (i.e., shorter) involucral bracts, as well as the inner ones, persistently appressed to ascending; plants 5–10 cm tall; involucres excluding the outer calyculus 12–16 mm tall
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  2b. Outer involucral bracts becoming reflexed [Fig. 471]; plants (1–) 5–75 cm tall; involucres excluding the outer calyculus (13–) 14–25 mm tall
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    T. officinale
    3a. Cypsela with a body (2–) 2.5–2.8 (–4) mm long that is muricate only in the apical  half [Fig. 472], with a beak 7–9 mm long; outermost involucral bracts (i.e., the reflexed ones) lanceolate
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    T. latilobum
    3b. Cypsela with a body 2.8–3.8 mm long that is usually muricate also in the basal half (sometimes all the way to the base), with a beak 8–12 mm long; outermost involucral bracts ovate to broad-lanceolate

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Show photos of: Each photo represents one species in this genus.