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- Carex swanii
Carex swanii — Swan's sedge
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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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Facts
This species was named for New England botanist Charles Walter Swan (1838-1921). It closely resembles ribbed sedge (Carex virescens).
Habitat
Forests, woodlands
Characteristics
- Habitat
- terrestrial
- New England state
-
- Connecticut
- Maine
- Massachusetts
- New Hampshire
- Rhode Island
- Vermont
- stem leaf blade width
- 1.5–3 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 has 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 is hairy
- Perigynium length
- 1.7–2.4 mm
- Leaf sheath color
- the leaf sheath is tinted pink, red or purple
- Leaf blade texture
- the leaf blade is hairy
- Perigynium beak teeth
- the perigynium beak is not divided at the tip into two teeth, or the teeth are very tiny
-
Flowers
- Anther length
- 0.7–1.6 mm
- Bumps on fruit
- there are no papillae on the perigynium surface
- Length of scale
- the scale is nearly as long as, or longer than, the perigynium
- Lowest spike length
- 5–19 mm
- Lowest spike width
- 2–4 mm
- Perigynium beak
- the perigynium has no beak, or an extremely short beak
- Perigynium beak length
- 0 mm
- Perigynium beak orientation
- NA
- Perigynium beak serrations
- NA
- 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
- green
- Perigynium cross-section
- the perigynium is trigonous (triangular) in cross-section
- Perigynium hairs
- the perigynium is hairy
- Perigynium length
- 1.7–2.4 mm
- Perigynium nerve number
- 5–13
- Perigynium nerve texture
- the nerves on the perigynium are raised, even after drying the perigynium
- Perigynium nerves lower side
- 2–6
- Perigynium nerves upper side
- 2–6
- Perigynium orientation
- the perigynia are oriented vertically or pressed against the axis or adjacent perigynia
- Perigynium puffy
- the perigynium is inflated (there is space between the perigynium and the achene)
- 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 orbicular (roughly circular, as wide as long)
- Perigynium width
- 1–1.5 mm
- Perigynium winged
- the perigynium has no wings
- 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 has an awn on it
- Scale awn texture
- the carpellate scale awn does not have teeth (it may or may not have hairs)
- Scale color
-
- green
- white or translucent
- Scale length
- 1.3–2.4 mm
- Scale tip
-
- the carpellate scale tip is acuminate (tapered to a narrow point)
- the carpellate scale tip is acute (has a sharp 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
- Staminate scale tip
-
- the staminate scale tip is acuminate (tapered to a narrow point)
- the staminate scale tip is obtuse (has a blunt point)
- Stigma branching
- the stigmas have three 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
- 1.4–1.8 mm
- Achene width
- 0.8–1.1 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 all produced from the base of the plant
- Leaf blade cross-section
- The leaf blade is folded lengthwise, with one prominent midvien
- Leaf blade texture
- the leaf blade is hairy
- 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 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 rough, or has hairs
- Lowest bract sheath
- the lowest bract has no sheath (or a very short sheath up to four millimeters in length)
- Lowest leaf blade width
- 1.5–3 mm
- Lowest leaf sheath texture
- the leaf sheath feels smooth (it may have soft hairs)
- stem leaf blade width
- 1.5–3 mm
-
Place
- Habitat
- terrestrial
- New England state
-
- Connecticut
- Maine
- Massachusetts
- New Hampshire
- Rhode Island
- Vermont
- Specific habitat
-
- forests
- woodlands
-
Stem, shoot, branch
- Plant height
- 15–75 cm
- Relative stem height
- the main stem is equal to or shorter than the leaves
- 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
Usually occurs in non-wetlands, but occasionally in wetlands. (Wetland indicator code: FACU)
New England distribution and conservation status
Distribution
- Connecticut
- present
- Maine
- present
- Massachusetts
- present
- New Hampshire
- present
- Rhode Island
- present
- Vermont
- present
Conservation status
Exact status definitions can vary from state to state. For details, please check with your state.
- Massachusetts
- widespread (S-rank: S5)
Native to North America?
Yes
Sometimes confused with
- Carex virescens:
- uppermost spike mostly 20-35 mm long and loosely flowered near the base (vs. C. swanii, with the uppermost spike mostly 11-20 mm long and densely flowered throughout).
Synonyms
- Carex virescens var. swanii Fern.
Family
Genus
From the dichotomous key of Flora Novae Angliae
160. Carex swanii (Fern.) Mackenzie N
Swan’s sedge. Carex virescens Muhl. ex Willd. var. swanii Fern. • CT, MA, ME, NH, RI, VT. Dry-mesic to mesic forests and woodlands.