Spartina alterniflora — smooth cordgrass

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

  one or 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)

In New England

From Flora Novae Angliae dichotomous key