Spartina alterniflora Loisel.

smooth cordgrass

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New England Distribution

Adapted from BONAP data

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North America Distribution

Adapted from BONAP data

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Facts About

Smooth cordgrass is the dominant grass species in salt marshes and coastal beaches of the Atlantic and Gulf coasts. It is also used extensively for coastal erosion control. It has been introduced to other parts of the world, including the west coast of the United States, where it is a threat to the native coastal plant communities.

Habitat

Brackish or salt marshes and flats, coastal beaches (sea beaches), marshes, wetland margins (edges of wetlands)

Characteristics

Habitat
  • aquatic
  • wetlands
New England state
  • Connecticut
  • Maine
  • Massachusetts
  • New Hampshire
  • Rhode Island
Leaf blade width
3–25 mm
Inflorescence branches
the flowers are attached to branches rather than to the main axis of the inflorescence
Spikelet length
8–14 mm
Glume relative length
both glumes are as long or longer than all of the florets
Awn on glume
the glume has no awn
One or more florets
there is one floret per spikelet
Lemma awn length
0 mm
Leaf sheath hair type
there are no hairs on the surface of the leaf sheath
Leaf ligule length
1–2 mm
Anther length
3–6 mm
Show All Characteristics
  • Flowers
    Anther length
    3–6 mm
    Anther number
    3
    Awn on glume
    the glume has no awn
    Bristles below spikelets
    no
    Floret lower bract texture
    the lemma is thin and flexible
    Floret number
    1
    Floret types within spikelet
    all the florets within a spikelet are similar
    Glume awn length
    0 mm
    Glume keel
    the glume keels are smooth and hairless
    Glume relative length
    both glumes are as long or longer than all of the florets
    Glume shape
    the glume is V-shaped in cross-section
    Glume veins
    1
    Glumes per spikelet
    2
    Inflorescence arrangement
    the spikelets are uniform
    Inflorescence axis orientation
    the inflorescence axis is straight
    Inflorescence branch length
    5–15 cm
    Inflorescence branches
    the flowers are attached to branches rather than to the main axis of the inflorescence
    Inflorescence branches coming off the lowest stem node
    1
    Inflorescence crowding
    the panicle is somewhat to very spread out, with clearly-evident branches
    Inflorescence length
    100–400 mm
    Inflorescence type (general)
    the spikelets are borne on stalks or on branches
    Inflorescence type (specific)
    the inflorescence is branched, and the branches do NOT both grow from the same side of the plant AND look like spikes
    Inforescence position
    the spikelets are mainly carried at the end of the stem
    Lemma awn base
    NA
    Lemma awn coiled
    NA
    Lemma awn length
    0 mm
    Lemma awn number
    the lemma has no awn
    Lemma awn orientation
    NA
    Lemma cross-section
    the lemma is V-shaped if you cut across the midpoint
    Lemma hairs
    the lemma is hairless between the veins
    Lemma surface
    the surface of the lemma is relatively smooth (not counting any longitudinal veins or hairs)
    Lemma tip
    the lemma tip is a simple point, with or without an awn (long narrow extension ending in a point)
    Lemma tip shape
    the lemma tip tapers to a long narrow point (it may or may not also have an awn or teeth at the tip)
    Lemma vein number
    • 1
    • 3
    Lower glume length
    4–10 mm
    Lower glume relative length
    the lower glume is one third to three quarters as long as the upper glume
    One or more florets
    there is one floret per spikelet
    Palea length
    10–12 mm
    Palea relative length
    palea is longer than lemma
    Reproductive system
    all the flowers on the plant have both carpels and stamens (synoecious)
    Spikelet axis length
    0 mm
    Spikelet axis tip
    there is no extension of the spikelet axis beyond the tip of the spikelet
    Spikelet disintegration
    the spikelet breaks off below the glumes
    Spikelet length
    8–14 mm
    Spikelet number per node
    0
    Spikelet pedicel
    the spikelets do not have pedicels
    Spikelet pedicel length
    0 mm
    Spikelet position
    the spikelets emerge from both the upper and lower halves of the inflorescence branches
    Spikelets per panicle branch
    10–30
    Spikelets spiny
    the spikelets do not appear spiny
    Tip of glume
    the tip of the glume is not divided (though it may have an awn on it)
    Upper glume length
    8–14 mm
    Upper glume relative length
    the upper glume is more than one half as long as the lowest lemma
  • Growth form
    Horizontal rooting stem
    no
    Lifespan
    the plant lives more than two years
    Rhizomes
    yes
    Roots
    the plant has rhizomes (horizontal underground stem with roots growing from it)
  • Leaves
    Basal leaves
    the plant has few or no leaves coming from the base of the flowering stem
    Leaf auricles
    the leaves do not have auricles
    Leaf blade cross-section
    the leaf blade is more or less flat in cross-section, or slightly folded or rolled inwards
    Leaf blade hairs
    • the leaf blade is hairless, but it may have tiny prickles that give it a sand-papery feel
    • the leaf blade is hairy
    Leaf blade length
    Up to 60 cm
    Leaf blade texture
    • the leaf blade is rough and sandpapery
    • the leaf blade is smooth, or it may have soft hairs
    Leaf blade width
    3–25 mm
    Leaf ligule length
    1–2 mm
    Leaf ligule type
    the leaf ligule is in the form of a membrane with fine hairs
    Leaf margin glands
    there are no glands along the edges of the leaf blade
    Leaf sheath closed around stem
    the margins of the leaf sheath are overlapping and not fused together except in the basal half (or less)
    Leaf sheath hair type
    there are no hairs on the surface of the leaf sheath
    Leaf sheath hairs
    there are no hairs on the surface of the leaf sheath
  • Place
    Habitat
    • aquatic
    • wetlands
    New England state
    • Connecticut
    • Maine
    • Massachusetts
    • New Hampshire
    • Rhode Island
    Specific habitat
    • brackish or salt marshes and flats
    • edges of wetlands
    • marshes
    • sea beaches
  • Stem, shoot, branch
    Hairs at nodes
    the stem nodes are hairless or they have very sparse hairs
    Plant height
    20–250 cm
    Stem hairs
    the stem is nearly to completely hairless
    Stem orientation
    the stems are upright
    Stem spacing
    • the stems grow close together in compact clusters or tufts
    • the stems grow singly or a few together (they may form diffuse colonies)
    Stem thickness at base
    0.3–20 mm

Wetland Status

Occurs only in wetlands. (Wetland indicator code: OBL)

New England Distribution and Conservation Status

Distribution

Connecticut
present
Maine
present
Massachusetts
present
New Hampshire
present
Rhode Island
present
Vermont
absent

Conservation Status

Exact status definitions can vary from state to state. For details, please check with your state.

Maine
unranked (S-rank: SNR)
Massachusetts
unranked (S-rank: SNR)

Native to North America?

Yes and no (some introduced)

Sometimes Confused With

Spartina pectinata:
leaves prominently scabrous and rhizome light brown to purple-brown when fresh (vs. S. alterniflora, with leaves smooth or slightly scabrous along apical margins and rhizome white when fresh).

Synonyms

  • Spartina alterniflora var. glabra (Muhl. ex Bigelow) Fern.

Family

Poaceae

Genus

Spartina

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Information from Dichotomous Key of Flora Novae Angliae

1.  Spartina alterniflora Loisel. N

smooth cordgrass. Spartina alterniflora Loisel. var. glabra (Muhl. ex Bigelow) Fern. • CT, MA, 
ME, NH, RI. Saline marshes, Atlantic coast beaches and strands.