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• Grass-like plants
• Sedges
• Carex aquatilis

Carex aquatilis — water sedge

Facts

In some areas of the United States, water sedge is an important source of food for large waterfowl and a fair source of food for ungulates and small mammals.

Habitat

Fens, marshes, meadows and fields, shores of rivers or lakes

Characteristics

• Flowers

  Bumps on fruit

  the perigynium surface has papillae on it

  Length of scale

  the scale is shorter than the perigynium

  Lowest spike length

  10–50 mm

  Lowest spike stalk length

  At least 0 mm

  Perigynium beak

  the perigynium has no beak, or an extremely short beak

  Perigynium beak length

  0.1–0.4 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

  green

  Perigynium cross-section

  • the perigynium is biconvex (convexly rounded on both sides, like a lens) in 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

  2–3.3 mm

  Perigynium nerve number

  0–4

  Perigynium nerve texture

  NA

  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 elliptic (widest near the middle and tapering at both ends)
  • the perigynium body is obovate (egg-shaped, but with the widest point above the middle of the leaf blade)

  Perigynium width

  1.25–1.75 mm

  Perigynium winged

  the perigynium has no wings

  Pollen- and seed-producing spikes

  some of the spikes produce perigynia

  Pollen-producing spike length

  10–50 mm

  Pollen-producing spike number

  1–4

  Scale awn

  The carpellate scale does not have an awn (it may have a short point)

  Scale awn texture

  NA

  Scale color

  • other
  • red-brown

  Scale tip

  • the carpellate scale tip is acute (has a sharp point)
  • the carpellate scale tip is obtuse (has a blunt 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

  Stigma branching

  the stigmas have two branches

  Top spike

  the uppermost spike contains only staminate flowers

• Fruits or seeds

  Achene dimples

  the achene has no folds or dimples

  Style persistence

  the style falls off the mature achenes

• Growth form

  Rhizomes

  there are long rhizomes present

• Leaves

  Leaf arrangement

  the leaves are mostly produced higher up on the plant

  Leaf blade cross-section

  • The leaf blade is folded lengthwise, with one prominent midvien
  • 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 bumps

  the upper surface of the leaf blade has papillae on it

  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
  • 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 smooth, and has no 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

  2.5–8 mm

  Lowest leaf sheath texture

  the leaf sheath feels smooth (it may have soft hairs)

  stem leaf blade width

  2.5–8 mm

• Place

  Habitat

  wetlands

  New England state

  • Connecticut
  • Maine
  • Massachusetts
  • Rhode Island
  • Vermont

  Specific habitat

  • fens
  • marshes
  • meadows or fields
  • shores of rivers or lakes

• Stem, shoot, branch

  Plant height

  20–150 cm

  Relative stem height

  • the main stem is equal to or shorter than the leaves
  • 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 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