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- Eriophorum
- Eriophorum angustifolium
Eriophorum angustifolium — tall cottonsedge
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Facts
Tall cottonsedge is found across the northern United States and Canada. In New England it occurs in Maine and New Hampshire in peaty soils, shorelines and temporary pools. Native Americans of Alaska used the roots, stems and seeds for food, and the stems for weaving mats.
Habitat
Bogs, fens, shores of rivers or lakes, wetland margins (edges of wetlands)
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
-
- Maine
- New Hampshire
- 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
- 1.5–8 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
- 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 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
- 2–5 mm
- Floral bristle color
- the bristles are white
- 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
- 5–10 mm
- Floral scale nerves
- 1
- Floral scale shape
-
- the floral scales are lanceolate (widest below the middle, and tapering at both ends)
- the floral scales are ovate (roughly egg-shaped)
- Floral scale translucent
- the floral scales are translucent
- 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
- Inflorescence crowding
- the inflorescence is at least somewhat spread out, with at least one branch coming from the main stem
- 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
- 3
- 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 beak length
- 0 mm
- 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 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 400 mm
- Leaf blade width
- 1.5–8 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
-
- terrestrial
- wetlands
- New England state
-
- Maine
- New Hampshire
- Specific habitat
-
- bogs
- edges of wetlands
- fens
- shores of rivers or lakes
-
Stem, shoot, branch
- Plant height
- 20–100 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
- 0.8–1.2 mm
Wetland status
Occurs only in wetlands. (Wetland indicator code: OBL)
In New England
Distribution
- Connecticut
- absent
- Maine
- present
- Massachusetts
- absent
- New Hampshire
- present
- Rhode Island
- absent
- Vermont
- absent
Conservation status
Exact status definitions can vary from state to state. For details, please check with your state.
- Maine
- unranked (S-rank: SNR)
- New Hampshire
- extremely rare (S-rank: S1), endangered (code: E)
Subspecies and varieties
Our subspecies is Eriophorum angustifolium Honckeny ssp. angustifolium.
From Flora Novae Angliae dichotomous key
1. Eriophorum angustifolium Honckeny ssp. angustifolium N
tall cottonsedge. ME, NH; also reported from VT by Hultén and Fries (1986), but specimens are unknown. Peatlands, shorelines, peaty soils around temporary pools.
Native to North America?
Yes
Sometimes confused with
- Eriophorum viridicarinatum:
- summit of leaf sheath not darkened and midrib of floral scales conspicuous near apex (vs. E. angustifolium, with the summit of leaf sheath darkened and midrib of floral scales inconspicuous near apex).