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- Carex haydenii
Carex haydenii — Hayden's sedge
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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
New England distribution
Adapted from BONAP data
Native: indigenous.
Non-native: introduced (intentionally or unintentionally); has become naturalized.
County documented: documented to exist in the county by evidence (herbarium specimen, photograph). Also covers those considered historical (not seen in 20 years).
State documented: documented to exist in the state, but not documented to a county within the state. Also covers those considered historical (not seen in 20 years).
Note: when native and non-native populations both exist in a county, only native status is shown on the map.
Found this plant? Take a photo and post a sighting.
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
-
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)
In New England
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)
From Flora Novae Angliae dichotomous key
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).
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.