Carex tetanica — rigid sedge
![Inflorescence: Carex tetanica. ~ By Arthur Haines. ~ Copyright © 2024 Arthur Haines. ~ arthur.d.haines[at]gmail.com](https://newfs.s3.amazonaws.com/taxon-images-1000s1000/Cyperaceae/carex-tetanica-in-ahaines-a.jpg)
![Inflorescence: Carex tetanica. ~ By Arthur Haines. ~ Copyright © 2024 Arthur Haines. ~ arthur.d.haines[at]gmail.com](https://newfs.s3.amazonaws.com/taxon-images-1000s1000/Cyperaceae/carex-tetanica-in-ahaines-c.jpg)
![Plant form: Carex tetanica. ~ By Arthur Haines. ~ Copyright © 2024 Arthur Haines. ~ arthur.d.haines[at]gmail.com](https://newfs.s3.amazonaws.com/taxon-images-1000s1000/Cyperaceae/carex-tetanica-ha-ahaines-b.jpg)
Copyright: various copyright holders. To reuse an image, please click it to see who you will need to contact.
Facts
Rigid sedge grows in mainly calcareous fens and wet meadows in Connecticut, Massachusetts and New Hampshire.
Habitat
Fens (calcium-rich wetlands), marshes, meadows and fields
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.
enlargeCharacteristics
- Habitat
- wetlands
- New England state
-
- Connecticut
- Massachusetts
- New Hampshire
- Leaf blade width
- 1.5–5 mm
- Lowest bract sheath
- the lowest bract has a sheath longer than four millimeters
- Spike on stalk
- the lowest spike on the plant has a peduncle
- Top spike
- the uppermost spike contains only staminate flowers
- Perigynium hairs
- the perigynium has no hairs
- Perigynium length
- 2.5–4 mm
- Leaf sheath color
-
- the leaf sheath has no pink, red or purple tinting
- the leaf sheath is tinted pink, red or purple
- Leaf blade texture
- the leaf blade is smooth and hairless, or rough and sandpapery
- Perigynium beak teeth
- the perigynium beak is not divided at the tip into two teeth, or the teeth are very tiny
-
Flowers
- Bumps on fruit
- the perigynium surface has papillae on it
- Inflorescence length
- 40–320 mm
- Length of scale
- the scale is shorter than the perigynium
- Lowest spike length
- 6–40 mm
- Lowest spike width
- 3–5.8 mm
- Perigynium beak
- the perigynium has a beak
- Perigynium beak length
- Up to 0.5 mm
- Perigynium beak orientation
- the beak of the perigynium is curved, or angled out from the perigynium
- Perigynium beak serrations
- the perigynium beak has no serrations
- Perigynium beak teeth
- the perigynium beak is not divided at the tip into two teeth, or the teeth are very tiny
- Perigynium beak teeth length
- 0 mm
- Perigynium color
-
- brown
- yellow
- Perigynium cross-section
- the perigynium is trigonous (triangular) in cross-section
- Perigynium hairs
- the perigynium has no hairs
- Perigynium length
- 2.5–4 mm
- Perigynium nerve texture
- the nerves on the perigynium are raised, even after drying the perigynium
- Perigynium orientation
-
- the perigynia are angled outwards
- 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)
- Perigynium width
- 1–1.2 mm
- Perigynium winged
- the perigynium has no wings
- Pollen- and seed-producing spikes
- some of the spikes produce perigynia
- Pollen-producing spike number
- 1
- Scale awn
-
- The carpellate scale does not have an awn (it may have a short point)
- the carpellate scale has an awn on it
- Scale awn texture
-
- NA
- the carpellate scale awn does not have teeth (it may or may not have hairs)
- Scale color
-
- brown
- purple to black
- Scale tip
- the carpellate scale tip is obtuse (has a blunt point)
- Spike on stalk
- the lowest spike on the plant has a peduncle
- Spike orientation
- the spikes are oriented vertically or pressed against the axis
- Spikes per stem
- 2-15
- Stigma branching
- the stigmas have three branches
- Top spike
- the uppermost spike contains only staminate flowers
-
Fruits or seeds
- Achene dimples
- the achene has no folds or dimples
- Achene length
- 1.8–3 mm
- Achene width
- 1.2–1.8 mm
- Style persistence
- the style falls off the mature achenes
-
Growth form
- Rhizomes
- there are long rhizomes present
-
Leaves
- Leaf arrangement
- the leaves are all produced from the base of the plant
- Leaf blade cross-section
- the leaf blade is flat or M-shaped, with two prominent side-veins
- Leaf blade length to width ratio
- 20–40
- Leaf blade texture
- the leaf blade is smooth and hairless, or rough and sandpapery
- Leaf blade width
- 1.5–5 mm
- 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
- the leaf sheath is tinted pink, red or purple
- 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
- 0.6–6 mm
- Lowest bract sheath
- the lowest bract has a sheath longer than four millimeters
- Lowest leaf blade width
- 1.5–5 mm
- Lowest leaf sheath texture
- the leaf sheath feels smooth (it may have soft hairs)
-
Place
- Habitat
- wetlands
- New England state
-
- Connecticut
- Massachusetts
- New Hampshire
- Specific habitat
-
- fens (calcium-rich wetlands)
- marshes
- meadows or fields
-
Stem, shoot, branch
- Plant height
- 15–65 cm
- Relative stem height
- the main stem is taller than the leaves
- Stem cross-section
- the main stem is roughly triangular in cross-section
- Stem spacing
- the stems grow singly or a few together (they may form diffuse colonies)
Wetland status
Usually occurs in wetlands, but occasionally in non-wetlands. (Wetland indicator code: FACW)
In New England
Distribution
- Connecticut
- present
- Maine
- absent
- Massachusetts
- present
- New Hampshire
- present
- Rhode Island
- absent
- Vermont
- absent
Conservation status
Exact status definitions can vary from state to state. For details, please check with your state.
- Connecticut
- uncommon (S-rank: S3)
- Massachusetts
- uncommon (S-rank: S3), special concern (code: SC)
- New Hampshire
- extirpated (S-rank: SX), -- (code: --)
From Flora Novae Angliae dichotomous key
128. Carex tetanica Schkuhr NC
rigid sedge. CT, MA, NH. Circumneutral fens, meadows, and graminoid marshes. Reports of Carex woodii Dewey in New England (e.g., Dowhan 1979, Seymour 1982) were based, in large part, on specimens of C. tetanica that showed slight anthocyanic suffusion of the lower, bladeless sheaths and shallow rhizomes. However, C. woodii shows deep anthocyanic suffusion of the lower, bladeless sheaths and shallow, relatively stout rhizomes that emit aerial shoots at ± regular intervals. Further, the specimens were collected from fens (typical for C. tetanica, atypical for C. woodii).