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Carex castanea — chestnut sedge

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Facts

Chestnut sedge is rare in New England, where it is found on calcareous river shores, lake shores and meadows.

Habitat

Fens (calcium-rich wetlands), floodplain (river or stream floodplains), meadows and fields, shores of rivers or lakes

New England distribution

Adapted from BONAP data

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North America distribution

Adapted from BONAP data

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Characteristics

Habitat
  • terrestrial
  • wetlands
New England state
  • Connecticut
  • Maine
  • Massachusetts
  • New Hampshire
  • Vermont
Leaf blade width
2.5–9 mm
Lowest bract sheath
  • the lowest bract has a sheath longer than four millimeters
  • the lowest bract has no sheath (or a very short sheath up to four millimeters in length)
Spike on stalk
the lowest spike on the plant has a peduncle
Top spike
the uppermost spike contains only staminate flowers
Perigynium hairs
the perigynium has no hairs
Perigynium length
2.5–5 mm
Leaf sheath color
the leaf sheath is tinted pink, red or purple
Leaf blade texture
the leaf blade is hairy
Perigynium beak teeth
the perigynium beak is divided at the top into two teeth
Show all characteristics
  • Flowers

    Bumps on fruit
    there are no papillae on the perigynium surface
    Distance between perigynia
    1 mm
    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
    8–25 mm
    Lowest spike stalk length
    10–20 mm
    Lowest spike width
    4–5 mm
    Perigynium beak
    the perigynium has a beak
    Perigynium beak length
    0.5–1.5 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
    0.5 mm
    Perigynium color
    green
    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
    2.5–5 mm
    Perigynium nerve number
    14–18
    Perigynium nerve texture
    the nerves on the perigynium are raised, even after drying the perigynium
    Perigynium nerves lower side
    5–7
    Perigynium nerves upper side
    5–7
    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)
    Perigynium width
    1.3–2.5 mm
    Perigynium winged
    the perigynium has no wings
    Pollen- and seed-producing spikes
    some of the spikes produce perigynia
    Pollen-producing spike length
    10–30 mm
    Pollen-producing spike number
    1
    Pollen-producing spike peduncle length
    0–5 mm
    Pollen-producing spike width
    1.4–4 mm
    Scale awn
    The carpellate scale does not have an awn (it may have a short point)
    Scale awn texture
    • the carpellate scale awn does not have teeth (it may or may not have hairs)
    • the carpellate scale awn has tiny teeth
    Scale color
    • green
    • red-brown
    • white or translucent
    Scale tip
    the carpellate scale tip is acute (has a sharp point)
    Spike on stalk
    the lowest spike on the plant has a peduncle
    Spike orientation
    • the spikes are angled outwards, or arched over
    • the spikes are bent downwards or droop downwards
    • 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 only staminate flowers
  • Fruits or seeds

    Achene dimples
    the achene has no folds or dimples
    Achene length
    1.5–2 mm
    Achene width
    1–1.5 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 mostly produced higher up on 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 hairy
    Leaf blade width
    2.5–9 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 red dots on the translucent tissues of the leaf sheathes
    Leaf sheath folds
    there are no corrugations on the leaf sheath
    Leaf sheath texture
    the leaf sheath feels rough, or has hairs
    Lowest bract sheath
    • the lowest bract has a sheath longer than four millimeters
    • the lowest bract has no sheath (or a very short sheath up to four millimeters in length)
    Lowest leaf blade width
    2.5–9 mm
    Lowest leaf sheath texture
    the leaf sheath feels smooth (it may have soft hairs)
  • Place

    Habitat
    • terrestrial
    • wetlands
    New England state
    • Connecticut
    • Maine
    • Massachusetts
    • New Hampshire
    • Vermont
    Specific habitat
    • fens (calcium-rich wetlands)
    • meadows or fields
    • river or stream floodplains
    • shores of rivers or lakes
  • Stem, shoot, branch

    Plant height
    40–90 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

Usually occurs in wetlands, but occasionally in non-wetlands. (Wetland indicator code: FACW)

In New England

Distribution

Connecticut
present
Maine
present
Massachusetts
present
New Hampshire
present
Rhode Island
absent
Vermont
present

Conservation status

Exact status definitions can vary from state to state. For details, please check with your state.

Connecticut
extremely rare (S-rank: S1), endangered (code: E)
Massachusetts
extremely rare (S-rank: S1), endangered (code: E)
New Hampshire
extremely rare (S-rank: S1), endangered (code: E)

From Flora Novae Angliae dichotomous key

88.  Carex castanea Wahlenb. N

chestnut sedge. Carex flexilis Rudge • CT, MA, ME, NH, VT. River shores, lake shores, fens, meadows, usually associated with high-pH bedrock.

87×88. Carex arctata × Carex castanea Carex ×‌knieskernii Dewey is a rare, largely sterile hybrid know from ME, NH. 
It has long spikes of intermediate width between the two parents (20–45 ×3–5 mm) 
and sparsely pubescent leaf blades (the hairs most abundant in the basal portion of 
the blade).

Native to North America?

Synonyms

  • Carex flexilis Rudge

Family

Cyperaceae

Genus

Carex