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- Carex Group 3
- Section Cyperoideae
- Carex hormathodes
Carex hormathodes — marsh straw sedge
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Facts
Marsh straw sedge inhabits Atlantic coast beaches, and saline to fresh-tidal marshes.
Habitat
Brackish or salt marshes and flats, coastal beaches (sea beaches), fresh tidal marshes or flats
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.
Found this plant? Take a photo and post a sighting.
Characteristics
- Habitat
- wetlands
- New England state
-
- Connecticut
- Maine
- Massachusetts
- New Hampshire
- Rhode Island
- stem leaf blade width
- 1–3 mm
- Lowest bract sheath
- the lowest bract has no sheath (or a very short sheath up to four millimeters in length)
- Spike on stalk
- the lowest spike on the plant is not borne on a peduncle
- Top spike
- the uppermost spike contains both staminate and carpellate flowers, with the staminate flowers located below the carpellate flowers
- Perigynium hairs
- the perigynium has no hairs
- Perigynium length
- 3.8–5.6 mm
- Leaf sheath color
- the leaf sheath has no pink, red or purple tinting
- Leaf blade texture
- the leaf blade is smooth and hairless, or rough and sandpapery
- Perigynium beak teeth
- the perigynium beak is divided at the top into two teeth
-
Flowers
- Bumps on fruit
-
- the perigynium surface has papillae on it
- there are no papillae on the perigynium surface
- Inflorescence length
- 25–60 mm
- Length of scale
- the scale is shorter than the perigynium
- Lowest spike length
- 6–15 mm
- Lowest spike stalk length
- 0 mm
- Lowest spike width
- 4–8 mm
- Perigynium beak
- the perigynium has a beak
- Perigynium beak orientation
- the beak of the perigynium is straight, and in line with the perigynium
- Perigynium beak serrations
-
- the perigynium beak has no serrations
- the perigynium beak has tiny serrations along the edges
- Perigynium beak teeth
- the perigynium beak is divided at the top into two teeth
- Perigynium color
-
- green
- tan
- Perigynium cross-section
-
- the perigynium is planoconvex (flat on one surface and rounded on the other) in cross-section
- the perigynium is relatively flat in cross-section
- Perigynium hairs
- the perigynium has no hairs
- Perigynium length
- 3.8–5.6 mm
- Perigynium nerve number
- At least 10
- Perigynium nerve texture
- the nerves on the perigynium are raised, even after drying the perigynium
- Perigynium nerves lower side
- At least 5
- Perigynium nerves upper side
- At least 5
- Perigynium orientation
- the perigynia are oriented vertically or pressed against the axis or adjacent perigynia
- Perigynium puffy
- the achene is tightly enclosed by the perigynium
- Perigynium shape
-
- the perigynium body is obovate (egg-shaped, but with the widest point above the middle of the leaf blade)
- the perigynium body is ovate (egg-shaped)
- Perigynium width
- 1.8–2.8 mm
- Perigynium winged
- the perigynium has wings on it
- Pollen- and seed-producing spikes
- some of the spikes produce perigynia
- Pollen-producing spike length
- 0 mm
- Pollen-producing spike number
- 0
- Pollen-producing spike peduncle length
- 0 mm
- Pollen-producing spike width
- 0 mm
- Scale awn
- The carpellate scale does not have an awn (it may have a short point)
- Scale awn texture
-
- NA
- the carpellate scale awn does not have teeth (it may or may not have hairs)
- Scale color
-
- green
- red-brown
- Scale length
- 3.5–4.9 mm
- Scale tip
- the carpellate scale tip is acuminate (tapered to a narrow point)
- Spike on stalk
- the lowest spike on the plant is not borne on a peduncle
- Spike orientation
- the spikes are bent downwards or droop downwards
- Spikes per stem
- 2-15
- Staminate scale tip
- the staminate scale tip is acuminate (tapered to a narrow point)
- Stigma branching
- the stigmas have two branches
- Top spike
- the uppermost spike contains both staminate and carpellate flowers, with the staminate flowers located below the carpellate flowers
-
Fruits or seeds
- Achene dimples
- the achene has no folds or dimples
- Achene length
- 1.5–1.8 mm
- Achene width
- 0.7–1.1 mm
- Style persistence
- the style falls off the mature achenes
-
Growth form
- Rhizomes
- there are no rhizomes, or the rhizomes are very short
-
Leaves
- Leaf arrangement
- the leaves are mostly produced higher up on the plant
- Leaf blade cross-section
- The leaf blade is folded lengthwise, with one prominent midvien
- Leaf blade length to width ratio
- 83–140
- Leaf blade texture
- the leaf blade is smooth and hairless, or rough and sandpapery
- Leaf bumps
- the upper surface of the leaf blade does not have papillae
- Leaf sheath bumps
- there are no papillae at the top edge of the leaf sheath
- Leaf sheath color
- the leaf sheath has no pink, red or purple tinting
- Leaf sheath dots
- there are no dots on the leaf sheathes
- Leaf sheath folds
- there are no corrugations on the leaf sheath
- Leaf sheath texture
- the leaf sheath feels smooth, and has no hairs
- Ligule length
- 2–4 mm
- Lowest bract sheath
- the lowest bract has no sheath (or a very short sheath up to four millimeters in length)
- Lowest leaf blade width
- 1–3 mm
- Lowest leaf sheath texture
- the leaf sheath feels smooth (it may have soft hairs)
- stem leaf blade width
- 1–3 mm
-
Place
- Habitat
- wetlands
- New England state
-
- Connecticut
- Maine
- Massachusetts
- New Hampshire
- Rhode Island
- Specific habitat
-
- brackish or salt marshes and flats
- fresh tidal marshes or flats
- sea beaches
-
Stem, shoot, branch
- Plant height
- 20–80 cm
- Relative stem height
- the main stem is taller than the leaves
- Spike internode length
- 2–18 mm
- Stem cross-section
- the main stem is roughly triangular in cross-section
- 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
- 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
- widespread (S-rank: S5)
- New Hampshire
- uncommon (S-rank: S3), W (code: W)
From Flora Novae Angliae dichotomous key
47. Carex hormathodes Fern. N
marsh straw sedge. Carex straminea Willd. ex Schkuhr var. invisa Boott • CT, MA, ME, NH, RI. Rocky or sandy beaches of the Atlantic coast and bays, and saline to fresh-tidal marshes.
Native to North America?
Yes
Sometimes confused with
- Carex straminea:
- beak of perigynium spreading, usually more than half of the length of the +/- orbicular body, and staminate portion of lateral spikes 2-6 mm long (vs. C. hormathodes, with beak of perigynium ascending, shorter than half the length of the narrow-ovate body, and staminate portion of lateral spikes shorter than 2 mm).
Synonyms
- Carex straminea var. invisa Boott