Published In:
Essai d'une Nouvelle Agrostographie 53, 161, 169, pl. 11, f. 2. 1812. ( Ess. Agrostogr.)   
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(Last Modified On 7/9/2009)
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Acceptance
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Accepted
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(Last Modified On 7/9/2009)
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3. Echinochloa crusgalli (L.) P. Beauv. (barnyard grass)
Pl. 162
d–h; Map 656
E. esculenta (A. Braun) H. Scholz
E. frumentacea Link
E. utilis Ohwi & Yab.
E. crusgalli ssp. utilis (Ohwi & Yab.) T. Koyama
E. frumentacea ssp. utilis (Ohwi & Yab.) Tzvelev
E. crusgalli var. frumentacea (Link) W. Wight
E. colonum (L.) Link var. frumentacea (Link) Ridl.
Flowering stems 15–150 cm long, slender to stout, erect or
ascending from often spreading bases, less commonly spreading. Leaf sheaths
glabrous (rarely with a few hairs at the tip). Leaf blades 4–30 cm long, 5–30
mm wide, glabrous (rarely with a few hairs at the base). Inflorescences 5–25 cm
long, the main primary branches 2–8 cm long, ascending to less commonly
spreading and relatively densely spaced (rarely spreading at maturity), mostly
strongly overlapping along the main axis, all but the uppermost with several
short, secondary branches (note that the branches usually have relatively long,
pustular‑based hairs that should not be confused with those present on
the spikelets, which usually lack pustular bases). Spikelets 2.8–4.4 mm long
(excluding the awns), elliptic‑ovate in outline, green to brown or dark
purple at maturity. Upper glume 2.6–4.2 mm long (excluding the awn, if
present), ovate, tapered at the tip to a sharp point or an awn less than 1 mm
long, sparsely to densely hairy, at least along the nerves, the hairs all or
mostly lacking pustular bases. Sterile floret with the palea well developed and
2/3–3/4 as long as the lemma, the lemma 2.6–4.4 mm long (excluding the awn, if
present), ovate, tapered at the tip to a sharp point or an awn 1–40 mm long,
sparsely to densely hairy, at least along the nerves, the hairs all or mostly
with pustular bases. Fertile floret with the lemma 2.5–4.0 mm long, up to 2
times as long as wide, ovate to elliptic‑ovate, the tip relatively soft,
wrinkled and tending to wither at maturity, bluntly to sharply but broadly
pointed, usually differentiated from the main body by a line of minute hairs
(visible only with 15¥ or
higher magnification) at the base (absent in some cultivated forms). Anthers
0.5–1.0 mm long. 2n=54. July–November.
Introduced, common nearly throughout the state (native of
Europe, Asia; naturalized widely in the U.S., Canada, Mexico). Margins of ponds and banks of streams; also pastures, fallow fields, crop fields,
ditches, levees, gardens, roadsides, railroads, and open, disturbed areas.
The taxonomy of the E. crusgalli complex is perhaps
the most confusing in the genus. At the one extreme, some authors (Arnow, 1987;
Swink and Wilhelm, 1994) treat the native E. muricata as part of an
expanded concept of E. crusgalli, but the introduced and native plants
appear relatively distinct morphologically, at least throughout much of their
midwestern ranges, with only occasional specimens that are difficult to place.
Also, although E. crusgalli and E. colonum appear amply distinct,
occasional specimens of the former are difficult to distinguish from the
latter. At the other extreme, some authors (Clayton and Renvoize, 1982;
Tsvelev, 1983; Scholz, 1992) have recognized a number of additional variants of
E. crusgalli as varieties, subspecies, or segregate species. In Missouri, the principal variants involved are two cultivated taxa that escape uncommonly,
the Japanese millet, E. esculenta (reported for Missouri by Mühlenbach
[1983] under the name E. utilis), and the Indian millet or billion‑dollar
grass, E. frumentacea (included by Steyermark [1963] as E. crusgalli
var. frumentacea). Both of these variants are grown for forage and grain
production and are relatively robust plants with overlapping, ascending
spikelike racemes of densely spaced, rather plump, awnless (or nearly so)
spikelets. They differ from one another in relatively slight details of
spikelet color and density. Interestingly, Yabuno (1962, 1966) suggested, based
upon cytological study of artificial hybrids, that although E. esculenta
is a cultivated derivative of E. crusgalli that was developed in eastern
Asia and Japan, E. frumentacea more probably evolved from plants of E.
colonum cultivated in southwestern Asia. This hypothesis requires
confirmation, especially as plants of the E. frumentacea variant
resemble E. crusgalli more closely than they do E. colonum
morphologically. After futile attempts to construct a meaningful key to
separate these taxa, it seems most prudent in the present treatment to combine
all of these plants under the name E. crusgalli, without taxonomic
recognition of any of the segregates.
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