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• Carex Group 5
• Section Acrocystis
• Carex tonsa

Carex tonsa — shaved sedge

Facts

There are two varieties of shaved sedge in New England, (Carex tonsa var. tonsa and C. tonsa var. rugosperma), with overlapping ranges in New England. They may be found growing together.

Habitat

Cliffs, balds, or ledges, forests, grassland, woodlands

Characteristics

• Flowers

  Anther length

  1.6–2.9 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

  4–10 mm

  Perigynium beak

  the perigynium has a beak

  Perigynium beak length

  0.9–2 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 divided at the top into two teeth

  Perigynium beak teeth length

  0.2–0.5 mm

  Perigynium color

  • brown
  • green

  Perigynium cross-section

  the perigynium is trigonous (triangular) in cross-section

  Perigynium hairs

  the perigynium is hairy

  Perigynium length

  3.1–4.7 mm

  Perigynium nerve number

  0–2

  Perigynium nerve texture

  NA

  Perigynium nerves lower side

  0

  Perigynium nerves upper side

  0

  Perigynium orientation

  • the perigynia are angled outwards
  • the perigynia are oriented vertically or pressed against the axis or adjacent perigynia

  Perigynium puffy

  the achene is tightly enclosed by the perigynium

  Perigynium shape

  the perigynium body is elliptic (widest near the middle and tapering at both ends)

  Perigynium width

  1.1–1.6 mm

  Perigynium winged

  the perigynium has no wings

  Pollen- and seed-producing spikes

  some of the spikes produce perigynia

  Pollen-producing spike length

  4.5–11.3 mm

  Pollen-producing spike number

  1

  Pollen-producing spike peduncle length

  0.8–15 mm

  Pollen-producing spike width

  1.1–3 mm

  Scale awn

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

  Scale awn texture

  NA

  Scale color

  • brown
  • red-brown

  Scale length

  2.9–4.1 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 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)
  • the staminate scale tip is obtuse (has a blunt point)

  Stigma branching

  the stigmas have three branches

  Top spike

  the uppermost spike contains only staminate flowers

• Fruits or seeds

  Achene dimples

  the achene has no folds or dimples

  Achene length

  1.6–2 mm

  Achene width

  1.2–1.6 mm

  Style persistence

  the style falls off 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 folded lengthwise, with one prominent midvien

  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
  • the upper surface of the leaf blade has papillae on it

  Leaf sheath bumps

  • the top edge of the leaf sheath has papillae on it
  • 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

  0.5–4.3 mm

  Lowest leaf sheath texture

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

  stem leaf blade width

  0.5–4.3 mm

• Place

  Habitat

  terrestrial

  New England state

  • Connecticut
  • Maine
  • Massachusetts
  • New Hampshire
  • Vermont

  Specific habitat

  • cliffs, balds, or ledges
  • forests
  • grasslands
  • woodlands

• Stem, shoot, branch

  Plant height

  4–16 cm

  Relative stem height

  the main stem is equal to or shorter 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

Not classified

New England distribution and conservation status

From the dichotomous key of Flora Novae Angliae