Spartina alterniflora

Loisel.
Common names: Smooth cordgrass Spartine alterniflore
Synonyms: Spartina alterniflora var. pilosa Spartina alterniflora var. glabra
Treatment appears in FNA Volume 25. Treatment on page 244.

Plants rhizomatous; rhizomes elongate, flaccid, white, scales inflated, not or only slightly imbricate. Culms to 250 cm tall, (0.3) 5-15 (20) mm thick, erect, solitary or in small clumps, succulent, glabrous, having an unpleasant, sulphurous odor when fresh. Sheaths mostly glabrous, throat glabrous or minutely pilose, lower sheaths often wrinkled; ligules 1-2 mm; blades to 60 cm long, 3-25 mm wide, lower blades shorter than those above, usually flat basally, becoming involute distally, abaxial surfaces glabrous, adaxial surfaces glabrous or sparsely pilose, margins usually smooth, sometimes slightly scabrous, apices attenuate. Panicles 10-40 cm, with 3-25 branches, often partially enclosed in the uppermost sheath; branches 5-15 cm, loosely appressed, not twisted, more or less equally subremote to moderately imbricate throughout the panicle, axes often prolonged beyond the distal spikelets, with 10-30 spikelets. Spikelets 8-14 mm, straight, usually divergent, more or less equally imbricate on all the branches. Glumes straight, sides usually glabrous, sometimes pilose near the base or appressed-pubescent, hairs to 0.3 mm; lower glumes 4-10 mm, acute; upper glumes 8-14 mm, keels glabrous, lateral-veins not present, apices acuminate to obtuse, occasionally apiculate; lemmas glabrous or sparsely pilose, apices usually acuminate; paleas slightly exceeding the lemmas, thin, papery, apices obtuse or rounded; anthers 3-6 mm. 2n = 62.

Distribution

Conn., N.J., N.Y., Wash., Del., Fla., N.H., Tex., La., N.C., S.C., Ala., Miss., R.I., Va., Calif., Ga., N.B., Nfld. and Labr. (Labr.), N.S., P.E.I., Que., Maine, Md., Mass., Oreg.

Discussion

Spartina alterniflora is found on muddy banks, usually of the intertidal zone, in eastern North and South America, but it is not known from Central America. In addition, it has become established on the west coast of North America, and in England and southeastern France. It hybridizes with S. maritima in Europe, with S. pectinata in Massachusetts, and with S. foliosa in California.

The rhizomes and scales of S. alterniflora have large air spaces, presumably an adaptation to the anaerobic soils of its usual habitat. Decaploid plants tend to be larger than octoploids, but they cannot be reliably distinguished without a chromosome count.

Spartina alterniflora is considered a serious threat to coastal ecosystems in Washington and California. It out-competes many of the native species in these habitats and frequently invades mud flats and channels, converting them to marshlands. Pure S. alterniflora grows within the lower elevational marsh zones in its native range but, in San Francisco Bay, its hybrids with S. foliosa grow both below and above the range of that species.

Spartina alterniflora is now a major weed problem in southeastern China (Normile 2004).

Lower Taxa

None.

"prolonged" is not a number."decumbent" is not a number.

... more about "Spartina alterniflora"
pilose +  and glabrous +
0.3 cm3 mm <br />0.003 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
rounded +, obtuse +  and acuminate +
Mary E. Barkworth +
Loisel. +
1 (?) +  and 3 (?) +
multiple +, , +  and single +
keeled +  and rounded +
rhizomatous +
not fused +
intravaginal +, extravaginal +, branching +  and basal +
swelling +
membranous +
not pseudopetiolate +
0 cm0 mm <br />0 m <br /> (60 cm600 mm <br />0.6 m <br />) +
pubescent +  and glabrous +
involute +  and flat +
0.3 cm3 mm <br />0.003 m <br /> (2.5 cm25 mm <br />0.025 m <br />) +
divergent +, whorled +, opposite +, alternate +  and arranged +
spikelike +
5 cm50 mm <br />0.05 m <br /> (15 cm150 mm <br />0.15 m <br />) +
triangular +  and dome--shaped +
membranous +
Smooth cordgrass +  and Spartine alterniflore +
in small clumps +  and solitary +
0 cm0 mm <br />0 m <br /> (250 cm2,500 mm <br />2.5 m <br />) +
unpleasant +
10 cm100 mm <br />0.1 m <br /> (350 cm3,500 mm <br />3.5 m <br />) +
succulent +
0.5 cm5 mm <br />0.005 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
Conn. +, N.J. +, N.Y. +, Wash. +, Del. +, Fla. +, N.H. +, Tex. +, La. +, N.C. +, S.C. +, Ala. +, Miss. +, R.I. +, Va. +, Calif. +, Ga. +, N.B. +, Nfld. and Labr. (Labr.) +, N.S. +, P.E.I. +, Que. +, Maine +, Md. +, Mass. +  and Oreg. +
not waisted +
capillary +
pistillate +  and staminate +
sometimes longer +
bisexual +  and fertile +
round +  and compressed +
reduced +
straight +
shorter or longer +
subtending +
unequal +
appressed-pubescent +
uncinate +
0 cm0 mm <br />0 m <br /> (0.03 cm0.3 mm <br />3.0e-4 m <br />) +
paniculate +  and racemose +
3 cm30 mm <br />0.03 m <br /> (70 cm700 mm <br />0.7 m <br />) +
hollow +  and solid +
not absent +
pilose +  and glabrous +
sometimes longer +
0.1 cm1 mm <br />0.001 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
membranous +
inconspicuous +
0.4 cm4 mm <br />0.004 m <br /> (1 cm10 mm <br />0.01 m <br />) +
concealed +  and prominent +
2 +  and 1 +
10 cm100 mm <br />0.1 m <br /> (40 cm400 mm <br />0.4 m <br />) +
dry +  and fleshy +
spikelike +
elongate +
normile2004a +
inflated +
pilose +  and glabrous +
imbricate +  and divergent +
10 +  and 30 +
compressed +
0.8 cm8 mm <br />0.008 m <br /> (1.4 cm14 mm <br />0.014 m <br />) +
1 +  and 3 +
compound +  and simple +
2 (?) +  and 3 (?) +
plumose +
Spartina alterniflora var. pilosa +  and Spartina alterniflora var. glabra +
Spartina alterniflora +
Spartina +
species +
pilose +  and glabrous +
membranous +
0.8 cm8 mm <br />0.008 m <br /> (1.4 cm14 mm <br />0.014 m <br />) +
7 (?) +  and 13 (?) +
aquatic +  and terrestrial +
dioecious +, monoecious +  and synoecious +