New York Natural Heritage Program
Creeping Spikerush
Eleocharis ambigens Fern.
Monocots

General Description [-]
Spikerushes consist of a simple stem (the leaves bladeless and inconspicuous), with the infloresence consisting of a solitary, many-scaled spikelet at the top of the stem. The perianth (sepals and petals), if present, is reduced to bristles. The base of the style is expanded into a tubercle, and is usually persistent on the fruit (achenes).

Eleocharis fallax is a perennial, mat-forming species with long rhizomes. The stems are round (often ridged in dry specimens), and 30 to 75 cm tall, with purplish bases. The leaf-sheaths are persistent with obtuse, firm, red tips. The spikelets are egg-shaped to rounded and 5 to 12 mm tall, and the floral scales are deciduous. There are 1 to 5, brown, stout, perianth bristles, unequal in length but none exceeding the achene. The achenes are either compressed 3-sided or thickly biconvex, with evident angles, and have an evidently pitted surface. The tubercles are whitish-brown, pyramid-shaped, and not depressed. (FNA 2002, Gleason and Cronquist 1991)

Best Life Stage for Proper Identification [-]
Specimens with complete stems and mature, intact fruits are needed for identification.
Creeping Spikerush Images
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The Best Time to See
Creeping Spikerush's fruits mature in July and persist into October.
J F M A M J J A S O N D
Fruiting
The time of year you would expect to find Creeping Spikerush fruiting (green shading) in New York.