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• Sedges
• Carex richardsonii

Carex richardsonii — Richardson's sedge

Facts

Richardson's sedge is common in Canada, and only sneaks into New England via a single site in Manchester, Vermont. This makes it highly vulnerable in New England, and this population is monitored regularly for negative impacts such as successional encroachment of woody plants, or damage by hikers.

Habitat

Woodlands

Characteristics

• Flowers

  Anther length

  2.1–2.6 mm

  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

  Lowest spike length

  10–20 mm

  Lowest spike stalk length

  Up to 70 mm

  Perigynium beak

  the perigynium has a beak

  Perigynium beak length

  0.2–0.5 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

  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

  0–0.8 mm

  Perigynium color

  • brown
  • 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 is hairy

  Perigynium length

  2.4–2.9 mm

  Perigynium nerve number

  0–4

  Perigynium nerve texture

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

  Perigynium nerves lower side

  0–2

  Perigynium nerves upper side

  0–2

  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 oblanceolate (lance-shaped, but with the widest point above the middle of the leaf blade)
  • the perigynium body is obovate (egg-shaped, but with the widest point above the middle of the leaf blade)

  Perigynium width

  1–1.3 mm

  Perigynium winged

  the perigynium has no wings

  Pollen- and seed-producing spikes

  some of the spikes produce perigynia

  Pollen-producing spike length

  17.4–23 mm

  Pollen-producing spike number

  0–1

  Pollen-producing spike peduncle length

  3.3–15.7 mm

  Pollen-producing spike width

  2.5–3.8 mm

  Scale awn

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

  Scale awn texture

  NA

  Scale color

  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

  Spike orientation

  the spikes are oriented vertically or pressed against the axis

  Spikes per stem

  2-15

  Staminate scale tip

  • the staminate scale tip is acuminate (tapered to a narrow point)
  • the staminate scale tip is acute (has a sharp point)

  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

  1.7–1.8 mm

  Achene width

  1.1–1.2 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

  61–111

  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 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 a sheath longer than four millimeters

  Lowest leaf blade width

  0.9–3.3 mm

  Lowest leaf sheath texture

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

  stem leaf blade width

  0.9–3.3 mm

• Place

  Habitat

  terrestrial

  New England state

  Vermont

  Specific habitat

  woodlands

• Stem, shoot, branch

  Plant height

  14–32 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

Occurs only in non-wetlands. (Wetland indicator code: UPL)

New England distribution and conservation status

From the dichotomous key of Flora Novae Angliae