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Carex rariflora — loose-flowered alpine sedge

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Facts

Loose-flowered alpine sedge has a northerly distribution, being found in Canada, Alaska and Greenland. In New England it is known only from one or two historical collections from Mt. Katahdin, ME.

Habitat

Alpine or subalpine zones, bogs

New England distribution

Adapted from BONAP data

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North America distribution

Adapted from BONAP data

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Characteristics

Habitat
  • terrestrial
  • wetlands
New England state
Maine
stem leaf blade width
1–2.5 mm
Lowest bract sheath
the lowest bract has no sheath (or a very short sheath up to four millimeters in length)
Spike on stalk
the lowest spike on the plant has a peduncle
Top spike
the uppermost spike contains only staminate flowers
Perigynium hairs
the perigynium has no hairs
Perigynium length
2.5–4.5 mm
Leaf sheath color
  • the leaf sheath has no pink, red or purple tinting
  • the leaf sheath is tinted pink, red or purple
Leaf blade texture
the leaf blade is smooth and hairless, or rough and sandpapery
Perigynium beak teeth
the perigynium beak is not divided at the tip into two teeth, or the teeth are very tiny
Show all characteristics
  • Flowers

    Anther length
    2–2.5 mm
    Bumps on fruit
    the perigynium surface has papillae on it
    Length of scale
    • the scale is nearly as long as, or longer than, the perigynium
    • the scale is shorter than the perigynium
    Lowest spike length
    6–15 mm
    Lowest spike width
    3.5–5 mm
    Perigynium beak
    the perigynium has a beak
    Perigynium beak length
    Up to 0.3 mm
    Perigynium beak orientation
    the beak of the perigynium is straight, and in line with the perigynium
    Perigynium beak serrations
    the perigynium beak has no serrations
    Perigynium beak teeth
    the perigynium beak is not divided at the tip into two teeth, or the teeth are very tiny
    Perigynium beak teeth length
    0 mm
    Perigynium color
    brown
    Perigynium cross-section
    • the perigynium is relatively round in cross-section
    • the perigynium is trigonous (triangular) in cross-section
    Perigynium hairs
    the perigynium has no hairs
    Perigynium length
    2.5–4.5 mm
    Perigynium nerve number
    3–14
    Perigynium nerve texture
    the nerves on the perigynium are raised, even after drying the perigynium
    Perigynium nerves lower side
    3–7
    Perigynium nerves upper side
    0–7
    Perigynium orientation
    the perigynia are oriented vertically or pressed against the axis or adjacent perigynia
    Perigynium puffy
    the perigynium is inflated (there is space between the perigynium and the achene)
    Perigynium shape
    • the perigynium body is elliptic (widest near the middle and tapering at both ends)
    • the perigynium body is ovate (egg-shaped)
    Perigynium width
    1.6–2 mm
    Perigynium winged
    the perigynium has no wings
    Pollen- and seed-producing spikes
    some of the spikes produce perigynia
    Pollen-producing spike length
    6–20 mm
    Pollen-producing spike number
    1
    Pollen-producing spike width
    1–2.5 mm
    Scale awn
    The carpellate scale does not have an awn (it may have a short point)
    Scale awn texture
    NA
    Scale color
    purple to black
    Scale length
    3–4.8 mm
    Scale tip
    the carpellate scale tip is obtuse (has a blunt point)
    Spike on stalk
    the lowest spike on the plant has a peduncle
    Spike orientation
    • the spikes are angled outwards, or arched over
    • the spikes are bent downwards or droop downwards
    Spikes per stem
    2-15
    Staminate scale tip
    • the staminate scale tip is acute (has a sharp point)
    • the staminate scale tip is obtuse (has a blunt point)
    Stigma branching
    the stigmas have three branches
    Top spike
    the uppermost spike contains only staminate flowers
  • Fruits or seeds

    Achene dimples
    the achene has no folds or dimples
    Style persistence
    the style falls off the mature achenes
  • Growth form

    Rhizomes
    there are no rhizomes, or the rhizomes are very short
  • Leaves

    Leaf arrangement
    the leaves are all produced from the base of the plant
    Leaf blade cross-section
    • The leaf blade is folded lengthwise, with one prominent midvien
    • the leaf blade is flat or M-shaped, with two prominent side-veins
    Leaf blade texture
    the leaf blade is smooth and hairless, or rough and sandpapery
    Leaf bumps
    the upper surface of the leaf blade does not have papillae
    Leaf sheath bumps
    there are no papillae at the top edge of the leaf sheath
    Leaf sheath color
    • the leaf sheath has no pink, red or purple tinting
    • the leaf sheath is tinted pink, red or purple
    Leaf sheath dots
    there are red dots on the translucent tissues of the leaf sheathes
    Leaf sheath folds
    there are no corrugations on the leaf sheath
    Leaf sheath texture
    the leaf sheath feels smooth, and has no hairs
    Lowest bract sheath
    the lowest bract has no sheath (or a very short sheath up to four millimeters in length)
    Lowest leaf blade width
    1–2.5 mm
    Lowest leaf sheath texture
    the leaf sheath feels smooth (it may have soft hairs)
    stem leaf blade width
    1–2.5 mm
  • Place

    Habitat
    • terrestrial
    • wetlands
    New England state
    Maine
    Specific habitat
    • alpine or subalpine zones
    • bogs
  • Stem, shoot, branch

    Plant height
    5–35 cm
    Relative stem height
    the main stem is taller than the leaves
    Spike internode length
    Up to 15 mm
    Stem cross-section
    the main stem is roughly triangular in cross-section
    Stem spacing
    the stems grow close together in compact clusters or tufts

Wetland status

Occurs only in wetlands. (Wetland indicator code: OBL)

In New England

Distribution

Connecticut
absent
Maine
present
Massachusetts
absent
New Hampshire
absent
Rhode Island
absent
Vermont
absent

Conservation status

Exact status definitions can vary from state to state. For details, please check with your state.

Maine
historical (S-rank: SH), potentially extirpated (code: PE)

From Flora Novae Angliae dichotomous key

108.  Carex rariflora (Wahlenb.) Sm. NC

loose-flowered alpine sedge. Carex limosa L.  var. rariflora Wahlenb. • ME. High-elevation heaths and boggy areas; known only from historical collections from Katahdin, Piscataquis County, ME.

Native to North America?

Yes

Sometimes confused with

Carex limosa:
stems aphyllopodic, without dead leaf remains at the base, lateral spikes with 8-30 perigynia, and perigynia acute at the apex (vs. C. rariflora, with stems phyllopodic, with dead leaf remains at the base, lateral spikes with 2-10 perigynia, and perigynia rounded to obtuse at the apex).

Synonyms

  • Carex limosa L. var. rariflora Wahlenb.

Family

Cyperaceae

Genus

Carex