Spikelets 3.5-5 mm. Lower glumes 1-2.6 mm; upper glumes3-5 mm; lower lemmas usually awned, awns 6-16 mm, occasionally unawned; anthers 0.5-1.1 mm.

Echinochloa muricata var. muricata is the common variety in eastern North America.

Annual herb 0.8 - 1.5 m tall

Leaves: alternate, two-ranked. Sheaths open, compressed. Ligules absent. Blades 1 - 27 cm long, 0.5 mm - 3 cm wide, usually over ten times longer than wide, linear to lance-shaped, flat, parallel-veined, with a prominent midrib.

Inflorescence: a terminal arrangement of spikelets (panicle), to 35 cm long, with an elongate and sometimes hairy axis. Primary branches spreading, distant, 2 - 8 cm long, often bearing secondary branches.

Fruit: a caryopsis, indehiscent, enclosed within the persistent lemma and palea, yellowish, 1 - 2.5 mm long, broadly egg-shaped to spherical.

Culm: upright or spreading, 0.8 - 1.5 m long, round in cross-section, sometimes rooting at the lower nodes, often developing short axillary shoots at the upper nodes when mature. Lower nodes sometimes minutely hairy.

Spikelets: densely crowded on angular branches, purple or purple-streaked, 3.5 - 5 mm long, flat on one side and convex on the other (plano-convex), with bumpy-based hairs.

Florets: two per spikelet. Lower florets sterile. Upper florets bisexual, compressed dorsally. Anthers three, 0.5 - 1 mm long. Stigmas red.

Glumes:: Lower glumes 1 - 2.5 mm long, membranous. Upper glumes about equal to spikelets, 3 - 5 mm long, membranous.

Lemmas:: Lower lemmas similar to upper glumes in texture and size, usually bristle-tipped (bristle to 1.5 cm long). Upper lemmas broadly reverse egg-shaped or circular with a leather-like, narrowing apex (tip membranous), rounded dorsally, leather-like.

Paleas:: Lower paleas well-developed.

Similar species: No information at this time.

Flowering: August to October

Habitat and ecology: Disturbed areas, often in moist soil.

Occurence in the Chicago region: native

Etymology: Echinochloa comes from the Greek words echinos, meaning hedgehog, and chloa, meaning grass, referring to the bristly spikelets of some species. Muricata means roughened.

Author: The Morton Arboretum

Spikelets 3.5 mm or more to the base of the awn or mucronate tip of the sterile lemma; sterile lemma with an awn 6-25 mm, or seldom awnless. (E. pungens)

Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.

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