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• Carex gynocrates

Carex gynocrates — northern bog sedge

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 (calcium-rich wetlands), swamps, woodlands

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 blade width

  5–20 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

  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)

• Place

  Habitat

  wetlands

  New England state

  Maine

  Specific habitat

  • fens (calcium-rich wetlands)
  • 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)

New England distribution and conservation status

From the dichotomous key of Flora Novae Angliae