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Carex haydenii — Hayden's sedge

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New England distribution

Adapted from BONAP data

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North America distribution

Adapted from BONAP data

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Facts

Hayden's sedge is found in open habitats with seasonally saturated soils and appears to be declining due to land use changes. It is similar to, and often confused with, tussock sedge (Carex stricta).

Habitat

Marshes, meadows and fields, shores of rivers or lakes

Characteristics

Habitat
  • terrestrial
  • wetlands
New England state
  • Connecticut
  • Maine
  • Massachusetts
  • New Hampshire
  • Rhode Island
  • Vermont
Leaf blade width
3–5 mm
Lowest bract sheath
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
  • the lowest spike on the plant is not borne on a peduncle
Top spike
the uppermost spike contains only staminate flowers
Perigynium hairs
the perigynium has no hairs
Perigynium length
1.5–2.8 mm
Leaf sheath color
  • the leaf sheath has no pink, red or purple tinting
  • the leaf sheath is tinted pink, red or purple
Leaf blade texture
the leaf blade is smooth and hairless, or rough and sandpapery
Perigynium beak teeth
the perigynium beak is not divided at the tip into two teeth, or the teeth are very tiny
Show all characteristics

  • Flowers

    Bumps on fruit
    the perigynium surface has papillae on it
    Length of scale
    the scale is nearly as long as, or longer than, the perigynium
    Lowest spike length
    10–50 mm
    Lowest spike stalk length
    At least 0 mm
    Lowest spike width
    4–6 mm
    Perigynium beak
    the perigynium has no beak, or an extremely short beak
    Perigynium beak length
    0.1–0.2 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
    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
    • brown
    • green
    Perigynium cross-section
    the perigynium is biconvex (convexly rounded on both sides, like a lens) in cross-section
    Perigynium hairs
    the perigynium has no hairs
    Perigynium length
    1.5–2.8 mm
    Perigynium nerve number
    0
    Perigynium nerve texture
    NA
    Perigynium nerves lower side
    0
    Perigynium nerves upper side
    0
    Perigynium orientation
    the perigynia are angled outwards
    Perigynium puffy
    the perigynium is inflated (there is space between the perigynium and the achene)
    Perigynium shape
    the perigynium body is obovate (egg-shaped, but with the widest point above the middle of the leaf blade)
    Perigynium width
    1.5–2 mm
    Perigynium winged
    the perigynium has no wings
    Pollen- and seed-producing spikes
    some of the spikes produce perigynia
    Pollen-producing spike length
    20–50 mm
    Pollen-producing spike number
    1–2
    Scale awn
    The carpellate scale does not have an awn (it may have a short point)
    Scale awn texture
    NA
    Scale color
    • red-brown
    • tan
    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 obtuse (has a blunt point)
    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
    • 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 smooth and hairless, or rough and sandpapery
    Leaf blade width
    3–5 mm
    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
    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 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 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
    3–5 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
    • Rhode Island
    • Vermont
    Specific habitat
    • marshes
    • meadows or fields
    • shores of rivers or lakes

  • Stem, shoot, branch

    Plant height
    30–115 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 wetlands. (Wetland indicator code: OBL)

New England distribution and conservation status

Distribution

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

Conservation status

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

Massachusetts
extremely rare to rare (S-rank: S1S2), #NAME? (code: #NAME?)
Vermont
rare (S-rank: S2)

Native to North America?

Yes

Sometimes confused with

Carex stricta:
leaves usually as tall as or taller than the flower stem and scales subtending the perigynia shorter than the perigynia (vs. C. haydenii, with leaves usually shorter than the flower stem and scales subtending the perigynia longer than the perigynia).

Synonyms

  • Carex stricta var. decora Bailey
  • Carex stricta var. haydenii (Dewey) Kükenth.

Family

Cyperaceae

Genus

Carex

Help

From the dichotomous key of Flora Novae Angliae

135.  Carex haydenii Dewey N

Hayden’s sedge. Carex stricta Lam. var. decora Bailey; C. stricta Lam. var. haydenii (Dewey) Kükenth. • CT, MA, ME, NH, RI, VT. Open areas with seasonally saturated soils such as river shores, graminoid marshes, meadows.

135×138. Carex haydenii × Carex nigra → This very rare sedge hybrid is known from MA. It is most similar to Carex nigra due to the dark carpellate scales and perigynia that are usually suffused with dark 
red-brown. However, the carpellate scales are acute to acuminate and usually at least reach the base of the perigynium beak varying to sometimes shortly surpassing the 
beak (vs. carpellate scales that are rounded to obtuse (rarely acute) at the apex that usually do not reach the base of the beak). The leaves of the hybrid are generally shorter and mostly don’t reach the base of the inflorescence (vs. commonly reaching the inflorescence to equaling the height of the plant).