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 gynocrates — northern bog sedge

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

Facts

Northern bog sedge has a circumboreal distribution, and is relatively common in the subarctic, but in New England it is found only in Maine, where it is quite rare. It inhabits evergreen swamps under northern white-cedar (Thuja occidentalis) and wooded fens. Northern bog sedge is fairly distinctive in having a long, horizontal rhizome from which it puts up occasional stems with a single few-flowered spike per stem.

Habitat

Fens, swamps, woodlands

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

Characteristics

Habitat
wetlands
New England state
Maine
stem leaf blade width
5–20 mm
Lowest bract sheath
NA
Spike on stalk
NA
Top spike
  • entirely carpellate
  • the uppermost spike contains both staminate and carpellate flowers, with the carpellate flowers located below, or intermixed with, the staminate flowers
  • the uppermost spike contains only staminate flowers
Perigynium hairs
the perigynium has no hairs
Perigynium length
2.9–3.4 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
Show all characteristics
  • Flowers

    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
    • the scale is shorter than the perigynium
    Lowest spike length
    5–14 mm
    Lowest spike stalk length
    0 mm
    Lowest spike width
    4–8 mm
    Perigynium beak
    the perigynium has a beak
    Perigynium beak length
    0.5 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
    • the perigynium beak has tiny serrations along the edges
    Perigynium beak teeth
    the perigynium beak is not divided at the tip into two teeth, or the teeth are very tiny
    Perigynium color
    brown
    Perigynium cross-section
    the perigynium is biconvex (convexly rounded on both sides, like a lens) in cross-section
    Perigynium hairs
    the perigynium has no hairs
    Perigynium length
    2.9–3.4 mm
    Perigynium nerve number
    17–20
    Perigynium nerve texture
    the nerves on the perigynium are raised, even after drying the perigynium
    Perigynium nerves lower side
    8–10
    Perigynium nerves upper side
    8–10
    Perigynium orientation
    • the perigynia are angled outwards
    • the perigynia are curved or bent downwards or backwards along the axis
    Perigynium puffy
    the achene is tightly enclosed by the perigynium
    Perigynium shape
    • the perigynium body is oblong (rectangular but with rounded ends)
    • the perigynium body is ovate (egg-shaped)
    Perigynium width
    1.2–1.7 mm
    Perigynium winged
    the perigynium has no wings
    Pollen- and seed-producing spikes
    • all the spikes produce only pollen
    • some of the spikes produce perigynia
    Pollen-producing spike length
    8–16 mm
    Pollen-producing spike number
    0–1
    Pollen-producing spike peduncle length
    0 mm
    Scale awn
    The carpellate scale does not have an awn (it may have a short point)
    Scale awn texture
    NA
    Scale color
    • brown
    • tan
    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
    NA
    Spike orientation
    the spikes are oriented vertically or pressed against the axis
    Spikes per stem
    1
    Stigma branching
    the stigmas have two branches
    Top spike
    • entirely carpellate
    • the uppermost spike contains both staminate and carpellate flowers, with the carpellate flowers located below, or intermixed with, the staminate flowers
    • the uppermost spike contains only staminate flowers
  • Fruits or seeds

    Achene dimples
    the achene has no folds or dimples
    Achene length
    1.5–1.7 mm
    Achene width
    1–1.2 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 folded lengthwise, with one prominent midvien
    Leaf blade length to width ratio
    67–214
    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
    Lowest bract sheath
    NA
    Lowest leaf blade width
    5–20 mm
    Lowest leaf sheath texture
    the leaf sheath feels smooth (it may have soft hairs)
    stem leaf blade width
    5–20 mm
  • Place

    Habitat
    wetlands
    New England state
    Maine
    Specific habitat
    • fens
    • swamps
    • woodlands
  • Stem, shoot, branch

    Plant height
    2–30 cm
    Relative stem height
    the main stem is taller than the leaves
    Spike internode length
    0 mm
    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

Occurs only in wetlands. (Wetland indicator code: OBL)

In New England

Distribution

Connecticut
absent
Maine
present
Massachusetts
absent
New Hampshire
absent
Rhode Island
absent
Vermont
absent

Conservation status

Exact status definitions can vary from state to state. For details, please check with your state.

Maine
rare (S-rank: S2), special concern (code: SC)

From Flora Novae Angliae dichotomous key

156.  Carex gynocrates Wormsk. ex Drej. NC

northern bog sedge. Carex dioica L. ssp. gynocrates (Wormsk. ex Drej.) Hultén; C. dioica L. var. gynocrates (Wormsk. ex Drej.) Ostenf. • ME. Evergreen swamps dominated by Thuja occidentalis, wooded fens.

Native to North America?

Yes

Sometimes confused with

Carex arctogena:
basal sheaths anthocyanic and carpellate scales obtuse at the apex (vs. C. gynocrates, with basal sheaths not anthocyanic and carpellate scales acute to acuminate at the apex).

Synonyms

  • Carex dioica L. ssp. gynocrates (Wormsk. ex Drej.) Hultén
  • Carex dioica L. var. gynocrates (Wormsk. ex Drej.) Ostenf.

Family

Cyperaceae

Genus

Carex