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• Trichophorum alpinum

Trichophorum alpinum — alpine bulrush, alpine clubsedge

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

Characteristics

• 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)

New England distribution and conservation status

From the dichotomous key of Flora Novae Angliae