Eleocharis acicularis (L.) Roemer & J.A. Schultes

needle spikesedge

Copyright: various copyright holders. To reuse an image, please click it to see who you will need to contact.

New England Distribution

Adapted from BONAP data

Found this plant? Take a photo and post a sighting.

North America Distribution

Adapted from BONAP data

enlarge

Facts About

Needle spike sedge is a widespread species that is abundant in much of its range. In New England it is found in stream and lake shores and open, wet sites in all states. It can form large rooted or floating mats.

Habitat

Floodplain (river or stream floodplains), lacustrine (in lakes or ponds), meadows and fields, riverine (in rivers or streams), shores of rivers or lakes

Characteristics

Habitat
  • aquatic
  • wetlands
New England state
  • Connecticut
  • Maine
  • Massachusetts
  • New Hampshire
  • Rhode Island
  • Vermont
Stem shape in cross-section
the stem is round or oval in cross-section
Leaf blade width
0 mm
Leaf blade cross-section
NA
Inflorescence position
the inflorescence is at the tip of the plant
Inflorescence branching
the inflorescence is on one or more stems with no branches
Fruit type (general)
the fruit is like a seed, and surrounded by scales
Fruit length
0.7–1.1 mm
Leaf position on plant
the attachment points of all the leaves are at or near the base of the plant
Perianth composition
  • there are bristles attached at the base of the achene
  • there is no perianth on the plant
Fruit cross-section
the fruit is triangular to terete (circular) in cross-section
Show All Characteristics
  • Flowers
    Anther color (dry)
    the anthers range in color from white to tan or yellow to yellow-brown
    Anther length
    0.7–1.5 mm
    Floral bristle color
    the bristles are pale brown to brown
    Floral bristle number
    1-4
    Floral bristle relative length
    • the bristles are between one tenth as long as the achene, and equal in length to the achene
    • there are no bristles, or they are very tiny (less than one tenth as long as 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
    1.5–3.5 mm
    Floral scale nerves
    • 0
    • 1
    Floral scale shape
    the floral scales are ovate (roughly egg-shaped)
    Floral scale translucent
    the floral scales are translucent
    Flower number per cluster
    • 2-5
    • 5-20
    Inflorescence bract angle
    NA
    Inflorescence bract number
    NA
    Inflorescence bract position (Sparganium)
    NA
    Inflorescence bracts
    NA
    Inflorescence branching
    the inflorescence is on one or more stems with no branches
    Inflorescence crowding
    • NA
    • the inflorescence is crowded together in one tight cluster
    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 is no perianth on the plant
    Stamen number
    3
    Stigma number
    3
    Style division
    the top two thirds of the style is divided
    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 or less as wide as the achene
    Achene tubercle width
    0.15–0.25 mm
    Capsule relative length
    NA
    Fruit cross-section
    the fruit is triangular to terete (circular) in cross-section
    Fruit length
    0.7–1.1 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
    0.05–0.2 mm
  • Growth form
    Lifespan
    the plant lives more than two years
    Rhizome thickness
    0.25–0.5 mm
    Underground organs
    • the plant has a rhizome (a horizontal underground stem with roots growing from it)
    • the plant has one or more swollen storage organs underground, such as bulbs or tubers
  • Leaves
    Auricle length
    0 mm
    Auricle texture
    NA
    Auricles
    there are no auricles on the leaf sheath
    Leaf blade cross-section
    NA
    Leaf blade length
    0 mm
    Leaf blade width
    0 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
    NA
    Leaf sheath hairs
    the leaf sheathes are without hairs
    Pedicel length (Typha)
    0 mm
    Stem leaf blade ligules
    NA
    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
    1–2 mm
  • Place
    Habitat
    • aquatic
    • wetlands
    New England state
    • Connecticut
    • Maine
    • Massachusetts
    • New Hampshire
    • Rhode Island
    • Vermont
    Specific habitat
    • in lakes or ponds
    • in rivers or streams
    • meadows or fields
    • river or stream floodplains
    • shores of rivers or lakes
  • Stem, shoot, branch
    Plant height
    1–60 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
    Stem thickness at midpoint
    0.2–0.7 mm

Wetland Status

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

New England Distribution and Conservation Status

Distribution

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

Conservation Status

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

Massachusetts
unranked (S-rank: SNR)

var. acicularis

Massachusetts
unranked (S-rank: SNR)

var. submersa

Massachusetts
unranked (S-rank: SNR)

Native to North America?

Yes

Sometimes Confused With

Eleocharis parvula:
tubercle +/- confluent with the apex of the achene and not appearing clearly distinct from it and achene body without evident longitudinal striations nor with fine cross-veins connecting the striations (vs. E. acicularis, with a tubercle clearly distinct from the achene and achene body with longitudinal striations and fine cross-veins connection the striations).

Synonyms

  • Eleocharis acicularis var. submersa (H.J. Nilss.) Svens.

Family

Cyperaceae

Genus

Eleocharis

Need Help?

Get Help

Information from Dichotomous Key of Flora Novae Angliae

1.  Eleocharis acicularis (L.) Roemer & J.A. Schultes N

needle spikesedge. Eleocharis acicularis (L.) Roemer & J.A. Schultes var. submersa (H.J. Nilss.) Svens. • CT, MA, ME, NH, RI, VT. Stream shores, lake shores, meadows, and open places with wet, bare soil.