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- Trichophorum alpinum
Trichophorum alpinum — alpine bulrush, alpine clubsedge
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Facts
Alpine clubsedge is a circumboreal species native across Canada and some northern states of the United States. It inhabits fens, streamsides and meadows, often in lime-rich situations. The mature perianth bristles look from a distance like freshly-fallen snow.
Habitat
Fens, 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.
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Characteristics
- Habitat
-
- aquatic
- 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
- Leaf blade width
- 0.4–0.5 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 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
- 1.2–1.6 mm
- Leaf position on plant
- the attachment points of all the leaves are at or near the base of the plant
- Perianth composition
-
- there are bristles attached at the base of the achene
- there are long, thin hairs attached at the base of the achene
- Fruit cross-section
- the fruit is lenticular (lens-shaped) in cross-section
-
Flowers
- Anther length
- 1.1–1.6 mm
- Floral bristle color
- the bristles are white
- Floral bristle number
- 5-7
- 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 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 opaque
- Flower number per cluster
- 5-20
- Inflorescence bract angle
- the bracts are vertical or angled only slightly outwards
- Inflorescence bract number
- there is just one bract on the inflorescence
- Inflorescence bract position (Sparganium)
- NA
- Inflorescence bracts
- there is only one bract, and it looks like a continuation of the stem
- Inflorescence branching
- the inflorescence is on one or more stems with no branches
- Inflorescence crowding
- NA
- 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 is one spike or raceme at the tip of the stem
- Perianth composition
-
- there are bristles attached at the base of the achene
- there are long, thin hairs 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 surface texture
- the achene is smooth (it has no detectable texture)
- Achene tubercle relative width
- NA
- Achene tubercle width
- 0 mm
- Capsule relative length
- NA
- Fruit cross-section
- the fruit is lenticular (lens-shaped) in cross-section
- Fruit length
- 1.2–1.6 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
- 6–9 mm
- Leaf blade width
- 0.4–0.5 mm
- Leaf form
- all the leaves hold their form out of water
- Leaf position on plant
- the attachment points of all the leaves are at or near the base of the plant
- 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 no leaves on the main stem, or there is a small tooth or tiny blade, or a leaf sheath with no blade
- Width of seed-producing inflorescence
- 2.2–3.5 mm
-
Place
- Habitat
-
- aquatic
- wetlands
- New England state
-
- Connecticut
- Maine
- Massachusetts
- New Hampshire
- Rhode Island
- Vermont
- Specific habitat
-
- fens
- meadows or fields
- shores of rivers or lakes
-
Stem, shoot, branch
- Plant height
- 10–40 cm
- Stem shape in cross-section
- the stem is roughly triangular in cross-section
- Stem texture near tip
- the edges of the stem feel rough near the tip
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.
- Connecticut
- historical (S-rank: SH), special concern, extirpated (code: SC*)
- Maine
- unranked (S-rank: SNR)
- Massachusetts
- fairly widespread (S-rank: S4)
- Rhode Island
- historical (S-rank: SH), state historical (code: SH)
From Flora Novae Angliae dichotomous key
1. Trichophorum alpinum (L.) Pers. N
alpine clubsedge. Baeothryon alpinum (L.) Egor.; Eriophorella alpina (L.) Holub; Eriophorum alpinum L.; Scirpus hudsonianus (Michx.) Fern. • CT, MA, ME, NH, RI, VT. Fens, wet rocks, stream shores, circumneutral meadows.
Native to North America?
Yes
Sometimes confused with
- Eriophorum vaginatum:
- perianth bristles numbering 10–25 per flower and spikelets 10–50 mm long in fruit, subtended by 10–15 sterile, basal scales (vs. T. alpinum, with perianth bristles mostly 6 in each flower and spikelets 5.4–8 mm tall in fruit, subtended by a solitary involucral bract that resembles an enlarged, basal scale).
Synonyms
- Baeothryon alpinum (L.) Egor.
- Eriophorella alpina (L.) Holub
- Eriophorum alpinum L.
- Scirpus hudsonianus (Michx.) Fern.