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Nabalus
See list of 6 species in this genusLeaf blade outline has been used for identification despite the fact it is unreliable for our species occurring in temperate forests and woodlands. Specimens based solely on vegetative collections should not be considered as adequately vouchered. Pappus bristles frequently break off and the bristle fragments can be found about the involucres. These bristles are sometimes misinterpreted as hairs on the involucres, leading to misidentification. The pappus bristles of Nabalus are minutely barbellate, the involucral bract hairs are smooth. Reference: Bogler (2006c).
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1a. Involucral bracts sparsely to densely long-hirsute (caution: sometimes only a few hairs are present on the involucre of N. serpentarius, look near the base of the inner involucral bracts) [Figs. 434,435]
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2a. Lower leaf blades simple, broad-oblanceolate to obovate, the middle and upper blades clasping; capitulescence tall and narrow, raceme-like; rays pink to purple (infrequently white); capitula with (9–) 11–29 flowers [Fig. 434]
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2b. Lower leaf blades pinnately or palmately lobed or simple and then ovate to elliptic, the middle and upper blades short-petioled or sessile, but not clasping; capitulescence broader, corymb- or panicle-like; rays yellow to yellow-white; capitula with 8–14 flowers [Fig. 435]
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1b. Involucral bracts glabrous except for minute, apical cilia [Fig. 436]
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3a. Each capitulum with 4–6 inner (i.e., longer) involucral bracts and 5 or 6 flowers
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3b. Each capitulum with 7–14 inner involucral bracts and 9–20 flowers [Fig. 436]
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4a. Pappus deep red-brown; rays white to pink to lavender
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4b. Pappus light brown to pale yellow-brown; rays green-yellow to yellow-white or white
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5a. Rays white; axis of capitulescence and often upper portion of stem villous-puberulent; involucral bracts black-green to black, the dark pigmentation resolvable as minute spots or streaks at high magnification (i.e., 30 × and higher); lower leaf blades simple, triangular-sagittate
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5b. Rays green-yellow to yellow-white; axis of capitulescence and stem glabrous; involucral bracts green to black, provided with minute, white, waxy papillae (view at 15 × or higher) or with minute, dark spots in exposed situations; lower leaf blades pinnately or palmately lobed
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Each photo represents one species in this genus.