Setaria pumila (Poir.) Roemer & Schultes

Family: Poaceae, Tribe: Paniceae

Pertinent Synonyms & Notes (particularly those used in California; go to GRIN for other synonyms)

only ssp. pumila occurs in California

Setaria glauca var. pumila (Poir.) Podp., Pennisetum glaucum (L.) R.Br.

Pertinent Common Names (particularly those used in California; go to GRIN for other common names)

yellow foxtail

Primary Disseminule Type


Description (diagnostics are in brown)

Spikelet subtended by fascicle of 4–12(15) bristles measuring 3–12 mm long, flexible, antrorsely scaberulous, glabrous. Disarticulation above the bristles. Spikelet pedicelled (oblong), ovate to broadly elliptic, dorsally compressed, plano-convex (D-shaped in profile), 3–3.5 mm long (ssp. pumila) x 1.5–2(2.2) mm wide x 1.2–1.6 mm thick, falling entire, consisting of one fertile floret and one basal sterile floret without rachilla extension.

Lower glume ± round, 1.5–2.1 mm long (0.3–0.7 length of spikelet), membranous, enwrapping base of spikelet, without keel, 3-veined, apex acute. Upper glume ovate, 2–2.3 mm long (0.4–0.7 length of spikelet), membranous, without keel, 5-veined, apex acute.

Sterile lemma similar to glumes (membranous), ovate, same length as spikelet, sulcate, 5-veined, apex acute. Sterile palea same length as sterile lemma.

Fertile lemma ovate, dorsally compressed, convex in profile, 1.5–3.5 mm long, whitish-yellow to brown, usually with satiny sheen, indurate, without keel, surface strongly and widely ridged transversely, margins involute, apex acute.

Fertile palea indurate, ridged, margins involute, surface minutely hairy near apex.

Caryopsis elliptic, 1.4–2 mm long x 0.9–1.1 mm wide, embryo ca. 0.75 length of caryopsis, hilum round.

Similar Species

Similar Species Comparison Chart

Risk Assessment (codes in yellow or red indicate cause for concern; assessments are current as of mid-2011; click AUQP, NZBORIC, or NZBPI for access to the most recent versions of these databases and possible assessment changes)