Your help is appreciated. We depend on donations to help keep this site free and up to date for you. Can you please help us?

Donate

Native Plant Trust: Go Botany Discover thousands of New England plants

Carex muehlenbergii — Muhlenberg's sedge

Copyright: various copyright holders. To reuse an image, please click it to see who you will need to contact.

New England distribution

Adapted from BONAP data

Found this plant? Take a photo and post a sighting.

North America distribution

Adapted from BONAP data

enlarge

Facts

Muhlenbern's sedge is rare in northern New England, being protected in Maine and Vermont. There are two varieties, distinguished by the length of the carpellate scales and perigynia.

Habitat

Forests, grassland, meadows and fields, woodlands

Characteristics

Habitat
terrestrial
New England state
  • Connecticut
  • Maine
  • Massachusetts
  • New Hampshire
  • Rhode Island
  • Vermont
stem leaf blade width
2–4 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 carpellate flowers located below, or intermixed with, the staminate flowers
Perigynium hairs
the perigynium has no hairs
Perigynium length
2.7–4.2 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
Show all characteristics

  • Flowers

    Anther length
    1.5–2.3 mm
    Bumps on fruit
    there are no papillae on the perigynium surface
    Inflorescence length
    15–40 mm
    Length of scale
    the scale is shorter than the perigynium
    Lowest spike length
    5–8 mm
    Lowest spike stalk length
    0 mm
    Perigynium beak
    the perigynium has a beak
    Perigynium beak length
    0.2–1.2 mm
    Perigynium beak orientation
    the beak of the perigynium is straight, and in line with the perigynium
    Perigynium beak serrations
    the perigynium beak has tiny serrations along the edges
    Perigynium beak teeth
    the perigynium beak is divided at the top into two teeth
    Perigynium beak teeth length
    0.2–0.5 mm
    Perigynium color
    • brown
    • green
    • yellow
    Perigynium cross-section
    the perigynium is planoconvex (flat on one surface and rounded on the other) in cross-section
    Perigynium hairs
    the perigynium has no hairs
    Perigynium length
    2.7–4.2 mm
    Perigynium nerve number
    9–24
    Perigynium nerve texture
    the nerves on the perigynium are raised, even after drying the perigynium
    Perigynium nerves lower side
    9–15
    Perigynium nerves upper side
    0–9
    Perigynium orientation
    • the perigynia are angled outwards
    • the perigynia are oriented vertically or pressed against the axis or adjacent perigynia
    Perigynium shape
    the perigynium body is ovate (egg-shaped)
    Perigynium width
    1.8–3 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 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 has tiny teeth
    Scale color
    • green
    • white or translucent
    Scale length
    2–3.6 mm
    Scale tip
    the carpellate scale tip is acute (has a sharp point)
    Spike on stalk
    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
    Stigma branching
    the stigmas have two branches
    Top spike
    the uppermost spike contains both staminate and carpellate flowers, with the carpellate flowers located below, or intermixed with, the staminate flowers

  • Fruits or seeds

    Achene dimples
    the achene has no folds or dimples
    Achene length
    1.8–2.2 mm
    Achene width
    1.8–2.1 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 smooth and hairless, or rough and sandpapery
    Leaf bumps
    the upper surface of the leaf blade has papillae on it
    Leaf sheath bumps
    the top edge of the leaf sheath has papillae on it
    Leaf sheath color
    the leaf sheath has no pink, red or purple tinting
    Leaf sheath dots
    there are white dots on the green tissues of the leaf sheathes
    Leaf sheath folds
    the leaf sheath has corrugations on it
    Leaf sheath texture
    the leaf sheath feels smooth, and has no hairs
    Ligule length
    Up to 3 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
    2–4 mm
    Lowest leaf sheath texture
    the leaf sheath feels smooth (it may have soft hairs)
    stem leaf blade width
    2–4 mm

  • Place

    Habitat
    terrestrial
    New England state
    • Connecticut
    • Maine
    • Massachusetts
    • New Hampshire
    • Rhode Island
    • Vermont
    Specific habitat
    • forests
    • grasslands
    • meadows or fields
    • woodlands

  • Stem, shoot, branch

    Plant height
    20–90 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

Not classified

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.

Maine
extremely rare (S-rank: S1), endangered (code: E)

var. enervis

Massachusetts
fairly widespread (S-rank: S4)
New Hampshire
unrankable (S-rank: SU), Ind (code: Ind)
Vermont
extremely rare (S-rank: S1), threatened (code: T)

var. muehlenbergii

Massachusetts
fairly widespread (S-rank: S4S5)
New Hampshire
uncommon (S-rank: S3), W (code: W)
Vermont
rare (S-rank: S2), threatened (code: T)

Native to North America?

Yes

Sometimes confused with

Carex spicata:
leaf ligules mostly 4-8 mm long, much longer than broad, and perigynia 4-5.5 mm long (vs. C. muehlenbergii, with leaf ligules up to 3 mm long, usually wider than long, and perigynia 2.7-4.2 mm long).
Carex mesochorea:
inflorescence dense, with highly congested spikes, 1-1.5 times as tall as wide, and achenes 1.3-1.5 mm wide (vs. C. muehlenbergii, with the inflorescence congested to elongate, usually more than 1.5 times as tall as wide, and achenes 1.8-2.1 mm wide).

Synonyms

  • Carex plana Mackenzie

Family

Cyperaceae

Genus

Carex

Help

From the dichotomous key of Flora Novae Angliae

148.  Carex muehlenbergii Schkuhr ex Willd. N

Muhlenberg’s sedge.  148b. Carex plana Mackenzie • CT, MA, ME, NH, RI, VT; rare to the 
north. Dry-mesic to xeric, open areas such as grasslands, sandy fields, woodlands, and 
forest openings.

1a.  Carpellate scales 2–2.5 mm long; perigynia 2.7–3.1 mm long, lacking veins adaxially 
 … 148a. C. muehlenbergii var. enervis Boott

1b.  Carpellate scales 2.5–3.6 mm long; perigynia 3–4.2 mm long, with 5–9 veins or veinless adaxially … 148b. C. muehlenbergii var. muehlenbergii

Variety muehlenbergii is known from CT, MA, ME, NH, RI, VT. Variety enervis is known from CT, MA, NH, RI, VT.