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- Carex Group 7
- Section Griseae
- Carex conoidea
Carex conoidea — open-field sedge
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Facts
Individuals of open-field sedge that appear dwarfed can be found in the northern portion of its range and in habitats where water levels fluctuate rapidly.
Habitat
Anthropogenic (man-made or disturbed habitats), meadows and fields, shores of rivers or lakes
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
-
- terrestrial
- wetlands
- New England state
-
- Connecticut
- Maine
- Massachusetts
- New Hampshire
- Rhode Island
- Vermont
- Leaf blade width
- 2.3–5.6 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
- the lowest spike on the plant is not borne on a peduncle
- Top spike
- the uppermost spike contains only staminate flowers
- Perigynium hairs
- the perigynium has no hairs
- Perigynium length
- 2.5–4.3 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 not divided at the tip into two teeth, or the teeth are very tiny
-
Flowers
- Anther length
- 1.8–3.6 mm
- Bumps on fruit
- there are no papillae on the perigynium surface
- Length of scale
- the scale is shorter than the perigynium
- Lowest spike length
- 5–29 mm
- Lowest spike stalk length
- At least 0 mm
- Lowest spike width
- 3.1–10.2 mm
- Perigynium beak
- the perigynium has no beak, or an extremely short beak
- Perigynium beak length
- 0–0.2 mm
- 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
- 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 relatively round in cross-section
- Perigynium hairs
- the perigynium has no hairs
- Perigynium length
- 2.5–4.3 mm
- Perigynium nerve number
- 17–25
- Perigynium nerve texture
- the nerves on the perigynium are flat or concave after drying
- Perigynium nerves lower side
- 8–12
- Perigynium nerves upper side
- 8–12
- 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 oblong (rectangular but with rounded ends)
- 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
- 1.2–1.8 mm
- Perigynium winged
- the perigynium has no wings
- Pollen- and seed-producing spikes
- some of the spikes produce perigynia
- Pollen-producing spike length
- 5–30 mm
- Pollen-producing spike number
- 1
- Pollen-producing spike peduncle length
- 2.9–103 mm
- Pollen-producing spike width
- 1–4.2 mm
- Scale awn
- the carpellate scale has an awn on it
- Scale awn texture
- the carpellate scale awn has tiny teeth
- Scale color
-
- red-brown
- white or translucent
- Scale length
- 2.4–4.7 mm
- Scale tip
- the carpellate scale tip is acuminate (tapered to a narrow point)
- Spike on stalk
-
- the lowest spike on the plant has a peduncle
- the lowest spike on the plant is not borne on 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 obtuse (has a blunt point)
- 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
- 1.8–2.6 mm
- Achene width
- 1–1.4 mm
- Style persistence
- the style falls off the mature achenes
-
Growth form
- Rhizomes
-
- there are long rhizomes present
- 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 flat or M-shaped, with two prominent side-veins
- Leaf blade texture
- the leaf blade is smooth and hairless, or rough and sandpapery
- Leaf blade width
- 2.3–5.6 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
- 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
- 0.8–3.7 mm
- Lowest bract sheath
- the lowest bract has a sheath longer than four millimeters
- Lowest leaf blade width
- 2.3–5.6 mm
- Lowest leaf sheath texture
- the leaf sheath feels smooth (it may have soft hairs)
-
Place
- Habitat
-
- terrestrial
- wetlands
- New England state
-
- Connecticut
- Maine
- Massachusetts
- New Hampshire
- Rhode Island
- Vermont
- Specific habitat
-
- man-made or disturbed habitats
- meadows or fields
- shores of rivers or lakes
-
Stem, shoot, branch
- Plant height
- 2–75 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 close together in compact clusters or tufts
Wetland status
Usually occurs in non-wetlands, but occasionally in wetlands. (Wetland indicator code: FACU)
In New England
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
- unranked (S-rank: SNR)
From Flora Novae Angliae dichotomous key
78. Carex conoidea Schkuhr ex Willd. N
open-field sedge. Carex katahdinensis Fern. • CT, MA, ME, NH, RI, VT. Meadows, river shores, lake shores, and open, wet, disturbed ground. Carex katahdinensis represents dwarfed individuals of C. conoidea that occur on northern ponds with fluctuating water levels. The dwarf stature appears to represent an adaptation for rapid completion of reproduction. Some specimens of C. conoidea with relatively fewer flowers in the spikes, especially those missing the basal leaf sheaths, can be confused with specimens of C. grisea. However, C. conoidea has narrower perigynia—(1.2–) 1.3–1.7 (–1.8) mm wide—and prominently scabrous staminate spike peduncles, whereas the perigynia of C. grisea are wider—(1.8–) 2–2.6 mm wide—and have a smooth or sparsely scabrous staminate spike peduncle. Carex conoidea is the only member of its section that routinely occurs in open habitats.