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• Rhynchospora capillacea

Rhynchospora capillacea — needle beaksedge

Facts

Needle beaksedge is a rare species of calcareous marshes, seeping cliffs and riverside seeps. There are a few populations known from each of Connecticut, Massachusetts, Maine, New Hampshire and Vermont, all of which rank the species as endangered. Succession, invasive species and changes in hydrology are potential threats to the remaining populations.

Habitat

Fens (calcium-rich wetlands), floodplain (river or stream floodplains), meadows and fields, shores of rivers or lakes, swamps

Characteristics

• Flowers

  Floral bristle color

  the bristles are slightly or strongly colored with reddish brown

  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 length

  4 mm

  Floral scale shape

  the floral scales are elliptic (widest in the middle and tapering toward each end)

  Floral scale translucent

  the floral scales are opaque

  Flower number per cluster

  • 1
  • 2-5

  Inflorescence bract angle

  the bracts are vertical or angled only slightly outwards

  Inflorescence bract number

  • there are six or more bracts per inflorescence
  • there are two to five bracts per inflorescence
  • there is just one bract on the 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 crowded together in one tight cluster

  Inflorescence position

  • the inflorescence emerges from an axil, or most of its parts do so
  • 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

  2

  Style division

  the style is divided nearly from the base

  floral bristle barbs

  the bristles have tiny barbs on them

  plantlets budding at flower bases

  no

• Fruits or seeds

  Achene beak length

  0 mm

  Achene surface texture

  the achene has stripes or ridges that run from end to end

  Achene tubercle relative width

  the tubercle is one half to two thirds as wide as the achene

  Capsule relative length

  NA

  Fruit cross-section

  • the fruit is biconvex or elliptic (widest in the middle and tapering to both ends) in cross-section
  • the fruit is lenticular (lens-shaped) in cross-section

  Fruit length

  1.5–2 mm

  Fruit type (general)

  the fruit is like a seed, and surrounded by scales

  Fruit type (specific)

  the fruit is an achene (dry, seed-like fruit) with a tubercle (a swelling or projection, usually of a different color or texture) on it

  Locules in capsule

  NA

  Seed length

  0 mm

  Seed tail relative length

  0 mm

  Seed tails

  NA

  Tubercle height

  0.8–1.7 mm

• Growth form

  Lifespan

  the plant lives more than two years

  Rhizome thickness

  Up to 1.5 mm

  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 width

  0.2–0.4 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 blades

  there are fully-developed leaves with leaf blades on the main stem

  Width of seed-producing inflorescence

  Up to 10 mm

• Place

  Habitat

  wetlands

  New England state

  • Connecticut
  • Maine
  • Massachusetts
  • New Hampshire
  • Vermont

  Specific habitat

  • fens (calcium-rich wetlands)
  • meadows or fields
  • river or stream floodplains
  • shores of rivers or lakes
  • swamps

• Stem, shoot, branch

  Plant height

  10–40 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 stem feels smooth 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