Vascular Plants of North Carolina
Account for Viviparous Spikerush - Eleocharis vivipara   Link
Members of Cyperaceae:
Members of Eleocharis with account distribution info or public map:
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Section 5 » Order Cyperales » Family Cyperaceae
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DistributionMostly the southern and southeastern Coastal Plain (absent from most of the northern portion), but rare in the Sandhills and the Outer Banks (Nags Head Woods).

Coastal Plain, southeastern VA to FL and LA.
AbundanceRather rare to uncommon. Apparently not as rare as once thought, because botanists no longer have to rely on fruiting plants for ID. Surprisingly, this is listed as a State Threatened species, despite now a minimum of 12 counties with specimens. The website editors suggest changing the State Rank from S1 to S2.
HabitatBlackwater stream impoundment ponds (often with peat moss), sinkhole ponds, floating peat mats along blackwater creeks (Tyrrell & Hyde counties).
PhenologyFlowering and fruiting July-September. Emersed plants, such as atop peat mats, usually produce normal, semierect stems, spikelets, and seeds. Within populations that float in the water, there usually are many stems that do not produce spikelets but instead grow vegetative shoots (proliferations) from the stem tips, and then do so again. Thus, it appears that the stems are branched twice in succession. See also E. microcarpa, whose stems may be branched only once or not at all.
IdentificationSee comments under Phenology. This is our only Eleocharis species whose stems branch twice.
Taxonomic CommentsNone

The genus Eleocharis, the spikerushes, are unusual members of the sedge family in that the culms (flowering stems) are round or oval (rarely triangular) in cross-section, rather than triangular in the great majority of our sedges. In addition, leaf blades are absent; just 1-2 basal sheaths are present at the base of the culm. There is a single, cylindrical or narrowly ovoid, spikelet of florets at the culm summit. Details of achene (seed) shape, color, ornamentation, bristle length, and beak (tubercle) shape and size, are critical ID factors.
Other Common Name(s)Sprouting Spikerush, Umbrella Hairgrass (in use by the aquarium trade)
State RankS1 [S2]
Global RankG5
State StatusT
US Status
USACE-agcpOBL link
USACE-empOBL link
County Map - click on a county to view source of record.
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B.A. SorrieTyrrell County, 2013, mass of plants stranded by New Lake Fork of Alligator River. TyrrellPhoto_natural
B.A. SorrieMoore County, 2012, Powell's Millpond.
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