Carex oklahomensis Mackenzie

Oklahoma sedge

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New England Distribution

Adapted from BONAP data

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North America Distribution

Adapted from BONAP data

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Facts About

Oklahoma sedge might be called a tourist in Maine, where it occurs as a non-native of moist roadsides, ditches and wet meadows. Its native distribution is in a narrow band from Texas to North Carolina.

Habitat

Anthropogenic (man-made or disturbed habitats), marshes, meadows and fields

Characteristics

Habitat
  • terrestrial
  • wetlands
New England state
Maine
stem leaf blade width
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 is not borne on a peduncle
Top spike
the uppermost spike contains both staminate and carpellate flowers, with the carpellate flowers located below, or intermixed with, the staminate flowers
Perigynium hairs
the perigynium has no hairs
Perigynium length
4–5 mm
Leaf sheath color
the leaf sheath has no pink, red or purple tinting
Leaf blade texture
the leaf blade is smooth and hairless, or rough and sandpapery
Perigynium beak teeth
the perigynium beak is divided at the top into two teeth
Show All Characteristics
  • Flowers
    Bumps on fruit
    there are no papillae on the perigynium surface
    Inflorescence length
    50–100 mm
    Length of scale
    • the scale is nearly as long as, or longer than, the perigynium
    • the scale is shorter than the perigynium
    Lowest spike stalk length
    0 mm
    Perigynium beak
    the perigynium has a beak
    Perigynium beak length
    Up to 2.5 mm
    Perigynium beak orientation
    the beak of the perigynium is straight, and in line with the perigynium
    Perigynium beak serrations
    the perigynium beak has tiny serrations along the edges
    Perigynium beak teeth
    the perigynium beak is divided at the top into two teeth
    Perigynium color
    • brown
    • tan
    Perigynium cross-section
    the perigynium is planoconvex (flat on one surface and rounded on the other) in cross-section
    Perigynium hairs
    the perigynium has no hairs
    Perigynium length
    4–5 mm
    Perigynium nerve number
    17–19
    Perigynium nerve texture
    the nerves on the perigynium are raised, even after drying the perigynium
    Perigynium nerves lower side
    10–12
    Perigynium nerves upper side
    7
    Perigynium orientation
    • the perigynia are angled outwards
    • the perigynia are oriented vertically or pressed against the axis or adjacent perigynia
    Perigynium puffy
    the achene is tightly enclosed by the perigynium
    Perigynium shape
    • the perigynium body is lanceolate (lance-shaped; widest below the middle and tapering at both ends)
    • the perigynium body is ovate (egg-shaped)
    Perigynium width
    1.7 mm
    Perigynium winged
    the perigynium has no wings
    Pollen- and seed-producing spikes
    some of the spikes produce perigynia
    Pollen-producing spike length
    0 mm
    Pollen-producing spike number
    0
    Pollen-producing spike peduncle length
    0 mm
    Pollen-producing spike width
    0 mm
    Scale awn
    The carpellate scale does not have an awn (it may have a short point)
    Scale awn texture
    NA
    Scale color
    • tan
    • white or translucent
    Scale tip
    the carpellate scale tip is acuminate (tapered to a narrow point)
    Spike on stalk
    the lowest spike on the plant is not borne on a peduncle
    Spike orientation
    the spikes are oriented vertically or pressed against the axis
    Spikes per stem
    • 2-15
    • more than 15
    Stigma branching
    the stigmas have two branches
    Top spike
    the uppermost spike contains both staminate and carpellate flowers, with the carpellate flowers located below, or intermixed with, the staminate flowers
  • Fruits or seeds
    Achene dimples
    the achene has no folds or dimples
    Achene length
    1.7 mm
    Achene width
    1.5 mm
    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 mostly produced higher up on the plant
    Leaf blade cross-section
    The leaf blade is folded lengthwise, with one prominent midvien
    Leaf blade length to width ratio
    Up to 150
    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
    Leaf sheath dots
    there are no dots on 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
    Ligule length
    Up to 4 mm
    Lowest bract sheath
    the lowest bract has no sheath (or a very short sheath up to four millimeters in length)
    Lowest leaf blade width
    5 mm
    Lowest leaf sheath texture
    the leaf sheath feels smooth (it may have soft hairs)
    stem leaf blade width
    5 mm
  • Place
    Habitat
    • terrestrial
    • wetlands
    New England state
    Maine
    Specific habitat
    • man-made or disturbed habitats
    • marshes
    • meadows or fields
  • Stem, shoot, branch
    Plant height
    Up to 80 cm
    Relative stem height
    the main stem is taller than the leaves
    Spike internode length
    Up to 10 mm
    Stem cross-section
    • the main stem has all three edges raised to narrow wing-like ridges
    • 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)

New England Distribution and Conservation Status

Distribution

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

Conservation Status

None

Native to North America?

Yes and no (some introduced)

Sometimes Confused With

Carex stipata:
lowermost leaves usually with well-developed blades and leaf sheaths corrugated on the surface opposite the leaf blade, not prolonged above the junction with the leaf blade (vs. C. oklahomensis, with the lowermost 2 or 3 leaves with highly reduced blades and leaf sheaths smooth on the surface opposite the leaf blade, prolonged above the junction with the leaf blade and forming a tube that surrounds the stem).

Synonyms

  • Carex stipata Muhl. ex Willd. var. oklahomensis (Mackenzie) Gleason

Family

Cyperaceae

Genus

Carex

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Information from Dichotomous Key of Flora Novae Angliae

194.  Carex oklahomensis Mackenzie E

Oklahoma sedge. Carex stipata Muhl. ex Willd. var. oklahomensis (Mackenzie) Gleason 
• ME. Moist roadsides, ditches, marshes, wet meadows.