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• Cyperaceae
• Rhynchospora
• Rhynchospora torreyana

Rhynchospora torreyana — Torrey's beaksedge

Facts

Torrey's beaksedge is a rare plant of coastal plain pond shores in Massachusetts and Rhode Island. It depends on fluctuating water levels to minimize competition with woody plants. The integrity of coastal plain ponds (and Torrye's beaksedge populations) is threatened by shoreline development, water table drawdown due to wells, eutrophication from fertilizer and septic runoff, and soil disturbance.

Habitat

Shores of rivers or lakes

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 between one tenth as long as the achene, and equal in length to 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

  2.5–3.5 mm

  Floral scale shape

  the floral scales are ovate (roughly egg-shaped)

  Flower number per cluster

  • 2-5
  • 5-20

  Inflorescence bract angle

  the bracts are vertical or angled only slightly outwards

  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 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

  • 2
  • 3

  Stigma number

  2

  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 tiny wrinkles that run cross-wise across the achene

  Achene tubercle relative width

  the tubercle is two thirds to about 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

  1.4–1.6 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

  0.2–0.5 mm

• Growth form

  Lifespan

  the plant lives more than two years

  Rhizome thickness

  0 mm

  Underground organs

  there are only slender roots on the plant

• 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
  • the leaf blade is triangular in cross-section

  Leaf blade width

  2–3 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

  10–30 mm

• Place

  Habitat

  • aquatic
  • wetlands

  New England state

  • Massachusetts
  • Rhode Island

  Specific habitat

  shores of rivers or lakes

• Stem, shoot, branch

  Plant height

  50–100 cm

  Stem shape 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

Usually occurs in wetlands, but occasionally in non-wetlands. (Wetland indicator code: FACW)

New England distribution and conservation status

From the dichotomous key of Flora Novae Angliae