Avena barbata Pott ex Link

Family: Poaceae, Tribe: Aveneae

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

Avena hirsuta Moench, A. sativa L. var. barbata (Pott ex Link) Fiori

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

slender oat

Primary Disseminule Type


Description (diagnostics are in brown)

Spikelets solitary, consisting of 2–3 fertile florets and a barren rachilla extension, lanceolate, laterally compressed, 16–30(50) mm long, breaking up at maturity, disarticulating below each fertile floret.

Glumes persistent, similar, 15–30 mm long (exceeding tips of florets), membranous and thinner than fertile lemma, without keels or awns, 7–9-veined, apices acuminate. Lower glume lanceolate. Upper glume elliptic, 1.2–1.4 length of adjacent fertile lemma.

Florets: rachilla persistent, pilose, callus obtuse, hairs 2–3 mm long, disarticulation scar elliptic to triangular.

Lemma lanceolate, 12–26 mm long, coriaceous, light brown, without keel, 9-veined, surface scabrous above awn, usually densely strigose below, apex bifid, teeth 2–4(6) mm long sporting bristles (sometimes called “lateral awns”) 3–12 mm long, awn dorsal, arising below the mid-point of the lemma, bent once, twisted and dark brown below bend, 20–60 mm long overall.

Palea 10–18 mm long, keels ciliolate.

Caryopsis 5–7 mm long x 0.8–1.3 mm wide, compressed dorsiventrally, ventrally longitudinally grooved, light brown, silky hairy, hilum linear.

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)