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- Beckmannia syzigachne
Beckmannia syzigachne — American slough grass
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Facts
American slough grass is a wetland annual grass native to Asia, and to the western and northern United States, but not to New England. It has been collected in Connecticut and Massachusetts. The specific name (syzigachne) is derived from Greek and means "jointed achene".
Habitat
Anthropogenic (man-made or disturbed habitats), marshes, meadows and fields, shores of rivers or lakes, swamps, wetland margins (edges of wetlands)
New England distribution
Adapted from BONAP data
Native: indigenous.
Non-native: introduced (intentionally or unintentionally); has become naturalized.
County documented: documented to exist in the county by evidence (herbarium specimen, photograph). Also covers those considered historical (not seen in 20 years).
State documented: documented to exist in the state, but not documented to a county within the state. Also covers those considered historical (not seen in 20 years).
Note: when native and non-native populations both exist in a county, only native status is shown on the map.
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Characteristics
- Habitat
- wetlands
- New England state
-
- Connecticut
- Maine
- Vermont
- Leaf blade width
- 4–20 mm
- Inflorescence branches
- the flowers are attached to branches rather than to the main axis of the inflorescence
- Spikelet length
- 2–3 mm
- Glume relative length
- neither glume is quite as long as all of the florets
- Awn on glume
- the glume has no awn
- One or more florets
-
- there is more than one floret per spikelet
- 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
- 5–11 mm
- Anther length
- 0.5–1.5 mm
-
Flowers
- Anther length
- 0.5–1.5 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
- 1–2
- Floret types within spikelet
- all the florets within a spikelet are similar
- Glume awn length
- 0 mm
- Glume relative length
- neither glume is quite as long as all of the florets
- Glume shape
- the glume is V-shaped in cross-section
- Glume veins
- 3
- Glumes per spikelet
- 2
- Inflorescence arrangement
- the spikelets are uniform
- Inflorescence axis orientation
- the inflorescence axis is straight
- Inflorescence branch length
- 1–2 cm
- Inflorescence branches
- the flowers are attached to branches rather than to the main axis of the inflorescence
- Inflorescence crowding
- the panicle is somewhat to very congested (crowded), and the branches may not be clearly seen without close inspection
- Inflorescence length
- 70–300 mm
- Inflorescence type (general)
- the spikelets are borne on stalks or on branches
- Inflorescence type (specific)
- the inflorescence is branched and the branches all 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 base hair length
- 0 mm
- Lemma base hairs
- the lemma is hairless or feels just a tiny bit rough at the base
- Lemma cross-section
- the lemma is flat or rounded if you cut across the midpoint
- Lemma hairs
- the lemma is hairless between the veins
- Lemma keel hairs
- NA
- 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
- 5
- Lower glume length
- 3–3.5 mm
- Lower glume relative length
- the lower glume is nearly as long, or as long as, the upper glume
- One or more florets
-
- there is more than one floret per spikelet
- there is one floret per spikelet
- Palea length
- 2.4–3.5 mm
- Palea relative length
- palea is one half to fully as long as lemma
- Reproductive system
- all the flowers on the plant have both carpels and stamens (synoecious)
- 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
- 2–3 mm
- Spikelet number per node
- 0
- Spikelet pedicel
-
- the spikelets do not have pedicels
- the spikelets have pedicels
- Spikelet pedicel length
- At least 0 mm
- Spikelet position
- the spikelets emerge from both the upper and lower halves of the inflorescence branches
- Spikelet shape
-
- the spikelets are orbicular (circular) in profile
- the spikelets are ovate (egg-shaped, widest below the middle with rounded ends) in profile
- 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
- 3–3.5 mm
- Upper glume relative length
- the upper glume is more than one half as long as the lowest lemma
- Upper glume shape
- the upper glume is widest above the middle
-
Fruits or seeds
- Seed length
- Up to 2 mm
-
Growth form
- Horizontal rooting stem
- no
- Lifespan
- the plant lives only a single year or less
- Rhizomes
- no
- Roots
- there are only slender roots on the plant
-
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 basal lobe hairy
- NA
- Leaf blade base
- the leaf is tapered gradually to the base
- 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
- Leaf blade length
- 10–25 cm
- Leaf blade texture
- the leaf blade is rough and sandpapery
- Leaf blade width
- 4–20 mm
- Leaf ligule length
- 5–11 mm
- Leaf ligule type
- the leaf ligule is in the form of a membrane
- 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
- Orientation of topmost leaf
- the flag leaf is held upright, or at less than a 45 degree angle out from the stem
-
Place
- Habitat
- wetlands
- New England state
-
- Connecticut
- Maine
- Vermont
- Specific habitat
-
- edges of wetlands
- man-made or disturbed habitats
- marshes
- meadows or fields
- shores of rivers or lakes
- swamps
-
Stem, shoot, branch
- Plant height
- 20–120 cm
- Roots at lower stem nodes
- no
- Stem node number
- 2–4
- Stem orientation
- the stems are upright
- Stem spacing
- the stems grow close together in compact clusters or tufts
Wetland status
Occurs only in wetlands. (Wetland indicator code: OBL)
In New England
Distribution
- Connecticut
- present
- Maine
- present
- Massachusetts
- absent
- New Hampshire
- absent
- Rhode Island
- absent
- Vermont
- present
Conservation status
None
From Flora Novae Angliae dichotomous key
1. Beckmannia syzigachne (Steud.) Fern. E
American slough grass. Beckmannia erucaeformis (L.) Host ssp. syzigachne (Steud.) Breitung; Panicum syzigachne Steud. • CT, ME, VT. Wet ditches, low meadows, shorelines, marshes, edges of swamps.
Native to North America?
Yes and no (some introduced)
Sometimes confused with
- Leptochloa fusca:
- spikelets clearly longer than wide, with 2-20 bisexual florets, and glumes not cross-wrinkled, their tips separate (vs. B. syzigachne, with spikelets nearly circular in outline, with 1 floret or 2 florets and then the upper one sterile, and glumes cross-wrinkled, their tips crossing).
Synonyms
- Beckmannia erucaeformis (L.) Host ssp. syzigachne (Steud.) Breitung
- Panicum syzigachne Steud.