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- Dichotomous Key
- Cyperaceae
- Eriophorum
- Eriophorum virginicum
Eriophorum virginicum — tawny cottonsedge
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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.
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Facts
Tawny cottonsedge is confined to northeastern North America, and is found in bogs, fens and wet meadows throughout New England. The bristles of this species are brownish-yellow while other cottonsedges (Eriophorum) have white bristles.
Habitat
Bogs, fens, meadows and fields
Characteristics
- Habitat
- wetlands
- New England state
-
- Connecticut
- Maine
- Massachusetts
- New Hampshire
- Rhode Island
- Vermont
- Stem shape in cross-section
-
- the stem is roughly triangular in cross-section
- the stem is round or oval in cross-section
- Leaf blade width
- 1.5–4 mm
- Leaf blade cross-section
- the leaf blade is flat or rolled in at the edges
- Inflorescence position
- the inflorescence is at the tip of the plant
- Inflorescence branching
-
- the inflorescence is branched
- the inflorescence is on one or more stems with no branches
- Fruit type (general)
-
- the fruit is like a seed, and surrounded by hairs
- the fruit is like a seed, and surrounded by scales
- Fruit length
- 2.5–4 mm
- Leaf position on plant
- some leaf attachment points are above the midpoint of the stem
- Perianth composition
- there are bristles attached at the base of the achene
- Fruit cross-section
- the fruit is triangular to terete (circular) in cross-section
-
Flowers
- Anther length
- 0.7–1.5 mm
- Floral bristle color
- the bristles are pale brown to brown
- Floral bristle number
- 8 or more
- Floral bristle relative length
- the bristles are longer than the achene
- Floral bristles
- the bristles are straight or slightly curved
- Floral scale hairs
- there are no hairs on the floral scales
- Floral scale length
- 4–5 mm
- Floral scale nerves
-
- 2-5
- 7 or more
- Floral scale shape
-
- the floral scales are oblong (rectangular but with rounded ends)
- the floral scales are ovate (roughly egg-shaped)
- Floral scale translucent
- the floral scales are opaque
- Flower number per cluster
-
- 5-20
- more than 20
- Inflorescence bract angle
- the bracts are vertical or angled only slightly outwards
- Inflorescence bract number
- there are two to five bracts per inflorescence
- Inflorescence bract position (Sparganium)
- NA
- Inflorescence bracts
- there are at least two bracts, and they are either flat or folded or rolled in at the edges
- Inflorescence branching
-
- the inflorescence is branched
- the inflorescence is on one or more stems with no branches
- Inflorescence crowding
- the inflorescence is crowded together in one tight cluster
- Inflorescence position
- the inflorescence is at the tip of the plant
- Inflorescence shape
- the aggregations within the inflorescence are roughly circular (not flattened) in cross-section
- Inflorescence type
- there are two or more flowers, spikes or flower clusters on a branched inflorescence
- Perianth composition
- there are bristles attached at the base of the achene
- Stamen number
- 1
- Stigma number
- 3
- Style division
- the top two thirds of the style is divided
- floral bristle barbs
- the bristles do not have barbs on them
-
Fruits or seeds
- Achene tubercle relative width
- NA
- Achene tubercle width
- 0 mm
- Capsule relative length
- NA
- Fruit cross-section
- the fruit is triangular to terete (circular) in cross-section
- Fruit length
- 2.5–4 mm
- Fruit type (general)
-
- the fruit is like a seed, and surrounded by hairs
- the fruit is like a seed, and surrounded by scales
- Fruit type (specific)
- the fruit is an achene (dry, seed-like fruit) without a tubercle (a swelling or projection, usually of a different color or texture)
- Locules in capsule
- NA
- Seed length
- 0 mm
- Seed tail relative length
- 0 mm
- Seed tails
- NA
- Tubercle height
- 0 mm
-
Growth form
- Lifespan
- the plant lives more than two years
- Underground organs
- the plant has a rhizome (a horizontal underground stem with roots growing from it)
-
Leaves
- Auricle length
- 0 mm
- Auricle texture
- NA
- Auricles
- there are no auricles on the leaf sheath
- Leaf blade cross-section
- the leaf blade is flat or rolled in at the edges
- Leaf blade length
- Up to 300 mm
- Leaf blade width
- 1.5–4 mm
- Leaf form
- all the leaves hold their form out of water
- Leaf position on plant
- some leaf attachment points are above the midpoint of the stem
- Leaf septa
- the leaf blades do not have transverse septa
- Leaf sheath hairs
- the leaf sheathes are without hairs
- Pedicel length (Typha)
- 0 mm
- Stem leaf blade ligules
- the plant has ligules at the leaf blade bases
- Stem leaf blades
- there are fully-developed leaves with leaf blades on the main stem
-
Place
- Habitat
- wetlands
- New England state
-
- Connecticut
- Maine
- Massachusetts
- New Hampshire
- Rhode Island
- Vermont
- Specific habitat
-
- bogs
- fens
- meadows or fields
-
Stem, shoot, branch
- Plant height
- 40–120 cm
- Stem shape in cross-section
-
- the stem is roughly triangular in cross-section
- the stem is round or oval in cross-section
- Stem texture near tip
- the edges of the stem feel rough near the tip
- Stem thickness at midpoint
- 0.6–1 mm
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.
- Maine
- unranked (S-rank: SNR)
- Massachusetts
- widespread (S-rank: S5)
From the dichotomous key of Flora Novae Angliae
5. Eriophorum virginicum L. N
tawny cottonsedge. CT, MA, ME, NH, RI, VT. Bogs, acidic fens, meadows.