Burke: Eleocharis acicularis vs. Eleocharis ovata

	Eleocharis acicularis	Eleocharis ovata
	needle spikerush	ovoid spikerush
Habit	Very slender perennial from slender, branching rhizomes, forming dense tufts; culms filiform, 3-12 cm. tall, the basal sheaths pale or purplish.	Tufted annual, the culms 0.5-5 dm. tall, ribbed, 0.5-2 mm. thick.
Leaves	Leaves all basal and reduced to sheaths.	Leaves all basal and reduced to sheaths.
Flowers	Spikelet solitary and terminal, 2.5-7 mm. long, 3- to 15-flowered; scales of the spikelets spirally arranged, 1.5-2.2 mm. long, translucent, with a greenish midrib and paler margins; perianth of 3-4 bristles, equaling the achene, or wanting; stamens 3; style trifid, thickened at the base.	Spikelets ovoid, 5-13 mm. long, many-flowered; scales of the spikelets spirally arranged, 1.7-2.5 mm. long, purplish or brownish with greenish mid-stripe and paler margins, the lowest one empty; perianth of 6-7 brownish bristles, equaling the achene or wanting; stigmas 2 or sometimes 3.
Fruits	Achenes white to pale gray, 0.7-1.1 mm. long, with a conic tubercle (the thickened base of the style), the body obovoid, longitudinally 8- to 18-ribbed.	Achenes lenticular, 1-1.5 mm. long, straw-colored to dark brown, smooth and shining.

	Eleocharis acicularis	Eleocharis ovata
Flowering time	June-September	June-September
Habitat	Marshes, muddy shores, and other wet places.	Marshes and other wet places, from sea level to moderate elevagtions in the mountains.
Distribution	Occurring on both sides of the Cascades crest in Washington; Alaska to California, east across North America to the Atlantic Coast; circumboreal. [WildflowerSearch map] [BONAP county map]	Occurring on both sides of the Cascades crest in Washington; British Columbia and Alberta to Oregon, also in Arizona, and from Oklahoma east to eastern North America. [WildflowerSearch map]
Origin	Native	Native
Conservation status	Not of concern	Not of concern
Sibling taxa	E. bella, E. bolanderi, E. coloradoensis, E. engelmannii, E. erythropoda, E. geniculata, E. macrostachya, E. mamillata, E. obtusa, E. ovata, E. palustris, E. parvula, E. quinqueflora, E. rostellata, E. suksdorfiana, E. uniglumis	E. acicularis, E. bella, E. bolanderi, E. coloradoensis, E. engelmannii, E. erythropoda, E. geniculata, E. macrostachya, E. mamillata, E. obtusa, E. palustris, E. parvula, E. quinqueflora, E. rostellata, E. suksdorfiana, E. uniglumis
Web links	Local floras: BC, CA, OR, WA Local Web sites: CalFlora, CalPhotos, Flora NW, PNW Herbaria WildflowerSearch iNaturalist (observations) USDA Plants Database LBJ Wildflower Center SEINet Plants of the World Online Encyclopedia of Life Wikipedia Google Image Search	Local floras: BC, CA, OR, WA Local Web sites: CalFlora, CalPhotos, Flora NW, PNW Herbaria WildflowerSearch iNaturalist (observations) USDA Plants Database LBJ Wildflower Center SEINet Plants of the World Online Encyclopedia of Life Wikipedia Google Image Search

Eleocharis acicularis

Eleocharis ovata

needle spikerush

ovoid spikerush

Habit

Very slender perennial from slender, branching rhizomes, forming dense tufts; culms filiform, 3-12 cm. tall, the basal sheaths pale or purplish.

Tufted annual, the culms 0.5-5 dm. tall, ribbed, 0.5-2 mm. thick.

Leaves

Leaves all basal and reduced to sheaths.

Flowers

Spikelet solitary and terminal, 2.5-7 mm. long, 3- to 15-flowered;

scales of the spikelets spirally arranged, 1.5-2.2 mm. long, translucent, with a greenish midrib and paler margins;

perianth of 3-4 bristles, equaling the achene, or wanting;

stamens 3;

style trifid, thickened at the base.

Spikelets ovoid, 5-13 mm. long, many-flowered;

scales of the spikelets spirally arranged, 1.7-2.5 mm. long, purplish or brownish with greenish mid-stripe and paler margins, the lowest one empty;

perianth of 6-7 brownish bristles, equaling the achene or wanting; stigmas 2 or sometimes 3.

Fruits

Achenes white to pale gray, 0.7-1.1 mm. long, with a conic tubercle (the thickened base of the style), the body obovoid, longitudinally 8- to 18-ribbed.

Achenes lenticular, 1-1.5 mm. long, straw-colored to dark brown, smooth and shining.

Eleocharis acicularis

Eleocharis ovata

Flowering time

June-September

Habitat

Marshes, muddy shores, and other wet places.

Marshes and other wet places, from sea level to moderate elevagtions in the mountains.

Distribution

Occurring on both sides of the Cascades crest in Washington; Alaska to California, east across North America to the Atlantic Coast; circumboreal.

[WildflowerSearch map]

[BONAP county map]

Occurring on both sides of the Cascades crest in Washington; British Columbia and Alberta to Oregon, also in Arizona, and from Oklahoma east to eastern North America.

[WildflowerSearch map]

Origin

Native

Conservation status

Not of concern

Sibling taxa