Echinochloa crus-pavonis |
Echinochloa colona |
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guleaf barnyard-grass, gulf barnyard grass, gulf cockspur grass |
awnless barnyard grass, jungle rice, jungle ricegrass, or jungle-rice, small barnyard grass, watergrass |
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Habit | Plants annual or short-lived perennials. | Plants annual; erect or decumbent, cespitose or spreading, rooting from the lower cauline nodes. | ||||
Culms | 30-150 cm; nodes glabrous. |
10-70 cm; lower nodes glabrous or hispid, hairs appressed; upper nodes glabrous. |
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Sheaths | glabrous, often purplish; ligules absent; blades 12-60 cm long, 10-25 mm wide, glabrous. |
glabrous; ligules absent, ligule region frequently brown-purple; blades 8-22 cm long, 3-6(10) mm wide, mostly glabrous, sometimes hispid, hairs papillose-based on or near the margins. |
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Panicles | 10-30 cm, erect or drooping, nodes sparsely hispid, hairs papillose-based, internodes glabrous; primary branches to 14 cm, nodes sometimes sparsely hispid, hairs papillose-based, internodes usually glabrous; secondary branches to 3 cm. |
2-12 cm, erect, rachises glabrous or sparsely hispid; primary branches 5-10, 0.7-2(4) cm, erect to ascending, spikelike, somewhat distant, without secondary branches, axes glabrous or sparsely hispid, hairs 1.5-2.5 mm, papillose-based. |
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Spikelets | 2.5-3.4 mm long, 1.2-1.4 mm wide, disarticulating at maturity. |
2-3 mm, disarticulating at maturity, pubescent to hispid, hairs usually not papillose-based, tips acute to cuspidate. |
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Lower glumes | about 1/2 as long as the spikelets; upper glumes about as long as the spikelets; lower florets usually sterile, occasionally staminate; lower lemmas unawned, similar to the upper glumes; lower paleas subequal to the lemmas; upper lemmas 2.6-2.9 mm, not or scarcely exceeding the upper glumes, elliptic, coriaceous portion rounded distally, passing abruptly into a sharply differentiated, membranous, soon-withering tip; anthers 0.7-0.8 mm. |
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Upper glumes | subequal to the spikelets; lower florets sterile; lower lemmas unawned or awned, awns 3-10(15) mm, curved; lower paleas absent, vestigial, or well-developed; upper lemmas narrowly elliptic, not or scarcely exceeding the upper glumes, acute or obtuse, with a well-differentiated, early-withering tip, glabrous or pubescent at the base of the tip, hairs not forming a line across the base; anthers 0.5-0.7 mm. |
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Caryopses | 1.2-1.5 mm long, 1-1.3 mm wide; embryos 50-70% as long as the caryopses. |
1.2-1.6 mm, whitish; embryos 63-83% as long as the caryopses. |
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2n | = 36. |
= 54. |
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Echinochloa crus-pavonis |
Echinochloa colona |
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Distribution |
AL; AR; AZ; CA; CO; FL; KS; LA; MD; MO; MS; NM; NV; OK; OR; TX; UT; PR
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AL; AR; AZ; CA; FL; GA; IL; KS; KY; LA; MA; MD; MO; MS; MT; NC; NJ; NM; OK; OR; PA; SC; TN; TX; VA; VT; WA; HI; PR; Virgin Islands
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Discussion | Echinochloa crus-pavonis is a native species found in scattered locations from British Columbia to Arizona, east to Florida, and south into South America. It favors marshes and wet places at lower elevations, often being found in the water. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Echinochloa colona is widespread in tropical and subtropical regions. It is adventive and weedy in North America, growing in low-lying, damp to wet, disturbed areas, including rice fields. The unbranched, rather widely-spaced panicle branches make this one of the easier species of Echinochloa to recognize. Hitchcock (1913) considered that 'colonum' was a non-declining contraction, but dictionaries of Linnaeus' time treated it as a declining adjective. Because Linnaeus was the first to name the species (as "Panicum colonum"), it seems best to follow the practice considered correct in his day; hence "E. colona". (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Key |
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Source | FNA vol. 25, p. 398. | FNA vol. 25, p. 398. | ||||
Parent taxa | Poaceae > subfam. Panicoideae > tribe Paniceae > Echinochloa | Poaceae > subfam. Panicoideae > tribe Paniceae > Echinochloa | ||||
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Subordinate taxa | ||||||
Synonyms | E. colonum | |||||
Name authority | unknown | (L.) Link | ||||
Web links |
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