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knot-root bristlegrass, knotroot foxtail, marsh bristle grass, yellow bristlegrass

barbed bristlegrass

Habit Plants perennial; rhizomatous, rhizomes short, knotty. Plants annual.
Culms

30-120 cm;

nodes glabrous.

30-100 cm;

nodes glabrous.

Sheaths

glabrous;

ligules shorter than 1 mm, of hairs;

blades to 25 cm long, 2-8 mm wide, flat, scabrous above.

mostly glabrous, margins ciliate distally;

ligules 1-2 mm, of hairs;

blades 5-15 mm wide, flat, abaxial surfaces scabrous, adaxial surfaces sparsely villous.

Panicles

3-8 (10) cm, of uniform width throughout their length, densely spikelike;

rachises scabro-hispid;

bristles 4-12, 2-12 mm, antrorsely barbed, yellow to purple.

5-15 cm, tapering to the apices, branches verticillate;

rachises antrorsely rough hispid, without villous hairs;

bristles solitary, 4-7 mm, antrorsely or retrorsely scabrous.

Spikelets

2-2.8 mm, elliptical and turgid.

2-2.3 mm.

Lower glumes

about 1/3 as long as the spikelets, 3-veined;

upper glumes 1/2 - 2/3 as long as the spikelets, 5-veined;

lower florets often staminate;

lower lemmas occasionally indurate and faintly transversely rugose;

lower paleas equaling the lower lemmas;

upper lemmas distinctly transversely rugose, often purple-tipped.

about 1/3 as long as the spikelets, obtuse, 1(3)-veined;

upper glumes nearly as long as the spikelets;

lower paleas about 1/2 as long as the spikelets, broad;

upper lemmas finely and transversely rugose;

upper paleas similar to the upper lemmas.

2n

= 36, 72.

= 36.

Setaria parviflora

Setaria verticilliformis

Distribution
from FNA
AL; AR; AZ; CA; CT; DC; DE; FL; GA; IA; ID; IL; IN; KS; KY; LA; MA; MD; MO; MS; NC; NJ; NM; NV; NY; OH; OK; OR; PA; RI; SC; TN; TX; UT; VA; WA; WV; HI; PR; Virgin Islands
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from FNA
AL; DC; MD; MO; NJ; NY; PA; WI
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Discussion

Setaria parviflora is a common, native species of moist ground. It is most frequent along the Atlantic and Gulf coasts, but it also grows from the Central Valley of California east through the central United States and southward through Mexico to Central America, as well as in the West Indies. The plant from Oregon was found on a ballast dump; the species is not established in that state.

Setaria parviflora is the most morphologically diverse and widely distributed of the indigenous perennial species of Setaria.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Setaria verticilliformis is a European adventive that has been found at scattered, mostly urban, locations in the United States.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Source FNA vol. 25, p. 556. FNA vol. 25, p. 554.
Parent taxa Poaceae > subfam. Panicoideae > tribe Paniceae > Setaria > subg. Setaria Poaceae > subfam. Panicoideae > tribe Paniceae > Setaria > subg. Setaria
Sibling taxa
S. adhaerans, S. arizonica, S. barbata, S. chapmanii, S. corrugata, S. faberi, S. grisebachii, S. italica, S. leucopila, S. liebmannii, S. macrosperma, S. macrostachya, S. magna, S. megaphylla, S. palmifolia, S. pumila, S. rariflora, S. reverchonii, S. scheelei, S. setosa, S. sphacelata, S. texana, S. verticillata, S. verticilliformis, S. villosissima, S. viridis
S. adhaerans, S. arizonica, S. barbata, S. chapmanii, S. corrugata, S. faberi, S. grisebachii, S. italica, S. leucopila, S. liebmannii, S. macrosperma, S. macrostachya, S. magna, S. megaphylla, S. palmifolia, S. parviflora, S. pumila, S. rariflora, S. reverchonii, S. scheelei, S. setosa, S. sphacelata, S. texana, S. verticillata, S. villosissima, S. viridis
Synonyms S. imberbis, S. gracilis, S. geniculata S. verticillata var. ambigua
Name authority (Poir.) Kerguelen Dumort.
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