Carex retrorsa — retrorse sedge

Characteristics

• Flowers

  Bumps on fruit

  there are no papillae on the perigynium surface

  Inflorescence length

  30–350 mm

  Length of scale

  the scale is shorter than the perigynium

  Lowest spike length

  15–50 mm

  Lowest spike stalk length

  At least 0 mm

  Lowest spike width

  15–20 mm

  Perigynium beak

  the perigynium has a beak

  Perigynium beak length

  2.1–4.5 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

  Perigynium beak teeth

  the perigynium beak is divided at the top into two teeth

  Perigynium beak teeth length

  0.3–1.1 mm

  Perigynium color

  • green
  • tan

  Perigynium cross-section

  • the perigynium is relatively round in cross-section
  • the perigynium is trigonous (triangular) in cross-section

  Perigynium hairs

  the perigynium has no hairs

  Perigynium length

  6–10 mm

  Perigynium nerve number

  6–13

  Perigynium nerve texture

  the nerves on the perigynium are raised, even after drying the perigynium

  Perigynium nerves lower side

  3–6

  Perigynium nerves upper side

  3–6

  Perigynium orientation

  • the perigynia are angled outwards
  • the perigynia are curved or bent downwards or backwards along the axis

  Perigynium puffy

  the perigynium is inflated (there is space between the perigynium and the achene)

  Perigynium shape

  the perigynium body is ovate (egg-shaped)

  Perigynium width

  1.6–3.4 mm

  Perigynium winged

  the perigynium has no wings

  Pollen- and seed-producing spikes

  some of the spikes produce perigynia

  Pollen-producing spike number

  1–3

  Scale awn

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

  Scale awn texture

  NA

  Scale color

  • brown
  • green

  Scale length

  2.4–4.5 mm

  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

  • 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 angled outwards, or arched over
  • the spikes are oriented vertically or pressed against the axis

  Spikes per stem

  2-15

  Stigma branching

  the stigmas have three branches

  Top spike

  • 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

  2 mm

  Style persistence

  the style stays on 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 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

  3–10 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 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

  3–10 mm

  Lowest leaf sheath texture

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

• Place

  Habitat

  wetlands

  New England state

  • Connecticut
  • Maine
  • Massachusetts
  • New Hampshire
  • Rhode Island
  • Vermont

  Specific habitat

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

• Stem, shoot, branch

  Plant height

  10–105 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 close together in compact clusters or tufts

Wetland status

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

In New England

From Flora Novae Angliae dichotomous key