Scientific Name
Eleocharis palustris (L.) Roem. & Schult. (Synonyms: Eleocharis macrostachya; Eleocharis smallii; Eleocharis xyridiformis)
Common Name(s)
Common spikerush, creeping spikerush
Tribe / Family Name
Cyperaceae
Flowering Period
June to September
Symbol
ELPA3
Description
Common spikerush is a native cool-season perennial rhizomatous grass-like plant that reproduces vegetatively from rhizomes and by seeds. Culms range from 10–100 cm in height and has an upright growth habit and is rounded in cross-section (it is not 3-angled like many other species within the Cyperaceae family). Inflorescence is a terminal spikelet 5–23 mm long with numerous flowers that are lanceolate in outline and brown or chestnut-colored. Scales are up to 4 mm long and spirally arranged with 1 or 2 (sometimes 3) empty scales at the base of the spikelet. Flowers displaying both male and female sexual organs with typically 4 (less often 5 or 6) barbed perianth bristles that shortly exceed the achenes. Stigmas 2. Fruits are achenes (achenes not enclosed in a perigynium), obovate, smooth, lenticular, and yellow to medium brown in color. Leaves are reduced to sheaths at the base of the culms.
General Info
This obligate wetland species can be found in wet meadows, seep springs, pond and stream margins, foothills, plains, and montane sites.
Similar Species
Common spikerush is very distinctive and not easily confused with other grass-like plants. However, its appearance may look similar to other spikerush (Eleocharis) species.
Picture of growth habit.
Close-up picture of spike inflorescence.
Illustration of common spikerush. USDA-NRCS PLANTS Database / Britton, N.L., and A. Brown. 1913. <i>An illustrated flora of the northern United States, Canada and the British Possessions. 3 vols</i>. Charles Scribner's Sons, New York. Vol. 1: 314.
Illustration of common spikerush. Glen Cole, 2017.