Plants annual. Culms 14-80 cm, usually glabrous, erect or geniculate at the base, with (1)2-4(5) nodes. Sheaths open; auricles ciliate; ligules 0.2-0.8 mm, membranous, truncate; blades 1.5-10 mm wide, linear to linear-lanceolate, flat, spreading. Inflorescences terminal, spikes, with 2-13 spikelets, usually with 1-3 rudimentary spikelets at the base; disarticulation either at the base of the spikes or in the rachis, the spikelets falling attached to the internodes above or below. Spikelets solitary at each node, 1/2-2(3) times the length of the internodes, tangential to the rachis, appressed or ascending, upper spikelet(s) sometimes sterile; fertile spikelets 5-15 mm, with 2-7 florets, distal florets often sterile. Glumes ovate to rectangular, rounded on the back, scabrous or pubescent, with several prominent veins, midveins smooth throughout, apices truncate, denticulate, or awned, sometimes indurate at maturity; lemmas rounded on the back, apices toothed, frequently awned; paleas chartaceous, 2-keeled, keels ciliate; anthers 3, 1.5-4 mm, not penicillate; ovaries with pubescent apices. Caryopses lanceolate to lanceolate-ovate. x = 7. The name is derived from from the Greek aigilops, a word which has multiple etymological interpretations [see Slageren 1994, pp. 19-20 and 118-119], including wild oats and several variants related to the Greek aigos, goat.

Aegilops has about 23 species and is native from the Mediterranean region to central Asia, as well as in the Canary Islands. It is sometimes included in Triticum, because the two form natural hybrids and both are involved in the evolution of the cultivated wheats, including Triticum aestivum. They are treated as distinct genera here, in keeping with past practice and their differing ecological attributes, Aegilops being a weedy genus.

Four species are established in the Flora region; only Aegilops cylindrica is widespread. The introductions occurred at the end of the nineteenth or beginning of the twentieth century. Three other species have been collected in the region, but are not known to have persisted.

NOTE: In the following key and descriptions, spike and spikelet lengths exclude the rudimentary spikelets and awns.

1.   Aegilops tauschii Coss.
Tausch's Goatgrass, Rough-Spiked Hardgrass

Culms 20-45 cm, geniculate at the base, usually forming many tillers. Sheaths with hyaline margins, lower cauline sheath margins usually ciliate; blades 6-20 cm long, 3-6 mm wide. Spikes 5.5-8.2 cm long, 0.3-0.6 cm wide, narrowly cylindrical to slightly moniliform, with 6-12 spikelets; rudimentary spikelets absent; disarticulation in the rachises, the spikelets falling attached to the internodes above. Spikelets 7-8 mm long, 3-4 mm wide, cylindrical, scabrous, with 2-5 florets, distal 2 florets sterile. Glumes 5-7 mm, coriaceous, scabrous, rims thickened, apices obtuse to truncate, minutely denticulate, unawned; lemmas 6-8 mm, toothed and usually awned, awns usually solitary, awns of the lower spikelets to 4 cm, awns of the apical spikelets to 5.5 cm. Caryopses 5-6 mm, adhering to the lemmas and paleas. Haplomes D. 2n = 14.

Aegilops tauschii is a weed of disturbed areas. In the Flora region, it is known only from Riverside County, California, Cochise County, Arizona, and an old collection from Westchester County, New York. It is native from the Caucasus and southern shores of the Caspian Sea, eastward to Kazakhstan and western China, and southward to Iraq and northwestern India.

2.   Aegilops ventricosa Tausch
Swollen Goatgrass, Belly-Shaped Hardgrass

Culms 25-70 cm, erect to slightly geniculate at the base, forming few-many tillers. Sheaths with hyaline margins, ciliate; blades 7-15 cm long, 3-6 mm wide. Spikes 5-12 cm long, 0.3-0.6 cm wide, distinctly moniliform, with 3-11 fertile spikelets; rudimentary spikelets usually absent, sometimes 1-2; disarticulation in the rachises, the spikelets falling attached to the internodes above. Spikelets 7-11 mm, urceolate, with 2-5 florets, distal 1-2 florets sterile. Glumes of lower spikelets mostly glabrous, veins setulose, apices truncate, with a sharply acute tooth to 3 mm; glumes of apical spikelets 7-8 mm, with a central tooth or awn flanked by 2 short teeth, central awns to 0.9 cm on the lower glumes, to 2 cm on the upper glumes; lemmas of lower spikelets 8-10 mm, adaxial surfaces velutinous, apices awned, awns 0.3-3 cm, solitary; lemmas of apical spikelets awned, awns to 4 cm. Caryopses 5-7 mm, adhering to the lemmas and paleas. Haplomes DN. 2n = 28.

In the Flora region, Aegilops ventricosa was collected once in Delaware. It is native to the Mediterranean area. The Arabic name, Oum el guemah, translates as mother of [durum] wheat. It occasionally forms hybrids with Triticum durum.

3.   Aegilops crassa Boiss.
Persian Goatgrass

Culms 30-50 cm, erect, slightly geniculate, with few-many tillers. Sheaths ciliate near the throat; blades 8-25 cm long, 3-4 mm wide. Spikes (4.5)6-10(13) cm long, 0.5-0.7 cm wide, moniliform, with (4)6-12 fertile spikelets; rudimentary spikelets usually absent, occasionally 1-2; disarticulation in the rachises, the spikelets falling attached to the internodes above. Spikelets 7-14 mm long, 4-7 mm wide, ovate, pubescent, with 4-7 florets, distal 2 florets sterile. Glumes 7-10 mm, coriaceous, adpressed-velutinous, 2-3-toothed; lemmas of lower spikelets 8-10 mm, toothed, usually awned; lemmas of apical spikelets awned, awns 3-8.5 cm, usually diverging. Caryopses about 7 mm, adhering to the lemmas and paleas. Haplomes DM, DDM. 2n = 28, 42.

The single record of Aegilops crassa for North America is a specimen collected from about the Yonkers Wood Mill [in Yonkers, New York] in 1898. The species is native from Egypt to central Asia.

4.   Aegilops cylindrica Host
Jointed Goatgrass

Culms 14-50 cm, erect to decumbent at the base, usually with many tillers. Sheaths with hyaline margins, sometimes ciliate; blades 3-15 cm long, 2-5 mm wide. Spikes 2.2-12 cm long, about 0.3 cm wide, narrowly cylindrical, 10-45 times longer than wide, with (2)3-8(12) fertile spikelets; rudimentary spikelets absent or 1-2; disarticulation initially at the base of the spikes and secondarily in the rachises, the spikelets remaining attached to the internodes above. Spikelets 9-12 mm, narrowly cylindrical, scabrous or pubescent, all fertile, with 3-5 florets, lower (1)2-3 florets fertile. Glumes of lower spikelets awned, awns 0.2-0.5 cm; glumes of apical spikelets 7-9 mm, scabrid, apices with a 3-6 cm awn usually flanked by 2 lateral teeth; lemmas of lower spikelets 9-10 mm, adaxial surfaces velutinous distally, apices mucronate or awned, awns 0.1-0.5 cm; lemmas of apical spikelets 1-awned, awns 4-8 cm, flanked by 2 teeth. Caryopses 6-7 mm, adhering to the lemmas and paleas. Haplomes DC. 2n = 28.

Aegilops cylindrica is a widespread weed in North America, being particularly troublesome in winter wheat. It usually grows in disturbed sites such as roadsides, fields, and along railroad tracks. It is native to the Mediterranean region and central Asia, and is adventive in other temperate countries. Hybrids with Triticum aestivum have been found in various parts of North America. Being sterile annuals, they do not persist.

5.   Aegilops triuncialis L.
Barbed Goatgrass

Culms 17-60 cm, geniculate to semiprostrate at the base, usually with several tillers. Sheaths with hyaline margins, lower cauline sheath margins usually ciliate; blades 1.5-7 cm long, 2-3 mm wide. Spikes 2.2-6 cm long, 0.4-0.5 cm wide, narrowly ellipsoid at the base, subcylindrical distally, with 2-7 fertile spikelets; rudimentary spikelets (2)3; disarticulation at the base of the spikes. Lower fertile spikelets 7-13 mm, lanceolate-ovate, with 3-5 florets, first 1-2 florets fertile; upper spikelets 7-9 mm, reduced. Glumes of lower spikelets 6-10 mm, 2-3-awned, awns 2.5-6 cm, glabrous, scabrous, or velutinous, if 3-awned the central awn often shorter than the lateral awns, sometimes reduced to a tooth; glumes of apical spikelets 6-8 mm, 3-awned, central awns 2.5-8 cm, longer than the lateral awns; lemmas 7-11 mm, with 2-3 teeth, if 3-toothed the central tooth the longest, sometimes extending into an up to 10 mm awn. Caryopses 5-8 mm, falling free from the lemmas and paleas. Haplomes UC. 2n = 28.

North American collections of Aegilops triuncialis are from disturbed sites, mostly roadsides and railroads, in California and western Nevada. The native range of the species extends from the Mediterranean area east to central Asia and south to Saudi Arabia. Specimens from the Flora region belong to Aegilops triuncialis var. triuncialis, which has apical spikelets with 5-8 cm central awns on the glumes and 2 well-developed 1-3 cm lateral awns, and lateral spikelets with 2-3 well-developed 1.5-6 cm awns. It differs from A. triuncialis var. persica (Boiss.) Eig, which has apical spikelets with 2-5 cm central awns on the glumes and 2 lateral awns of 1-2 cm, sometimes reduced to teeth, and lateral spikelets with 1 awn to 1.5 cm and 1-2 teeth.

6.   Aegilops geniculata Roth
Ovate Goatgrass

Culms 20-40 cm, geniculate at the base, usually with many tillers. Sheaths with hyaline margins, distal portion of the lower cauline sheaths ciliate; blades 2-7.5 cm long, 2-5 mm wide. Spikes 1-3 cm long, 0.4-0.7 cm wide, narrowly ovoid to ellipsoid, widest basally, with (2)3-4 spikelets, distal spikelet sterile; rudimentary spikelets 1(2); disarticulation at the base of the spikes, above the rudimentary spikelets. Basal spikelets 7-10 mm long, 3-4 mm wide, urceolate, lower spikelet with 3-4 florets, lower 1-2 florets fertile; apical spikelets 4-5 mm long, 1-2 mm wide, narrowly obovoid, with 1 floret, florets reduced, sterile. Glumes of lower spikelets 6-10 mm, ovate, smooth, scabrous, appressed-velutinous, (3)4(5)-awned, awns 2-4.5 cm; glumes of apical spikelets about 3 mm, 4-awned, awns usually 1-3.5 cm; lemma of fertile florets 6-8 mm, adaxial surfaces often velutinous distally, apices 2-3-awned, awns 1-2.5 cm. Caryopses 4-6 mm, falling free from the lemmas and paleas. Haplomes MU. 2n = 28.

In the Flora region, Aegilops geniculata is known only from Mendocino County, California, where it usually occurs along roadsides. It is native from the Mediterranean area to central Asia. In California it grows in silty clay.

7.   Aegilops neglecta Req. ex Bertol.
Three-Awned Goatgrass

Culms 20-55 cm, geniculate and semiprostrate at the base, usually with many tillers. Sheaths with hyaline margins, ciliate; blades 5-8 cm long, 3-4 mm wide. Spikes 2-4.5 cm long, 0.4-1.3 cm wide, ovoid-ellipsoid basally, abruptly contracted distally to a narrow cylinder, with 3-6 spikelets, distal 1-3 spikelets sterile; rudimentary spikelets (2)3; disarticulation at the base of the spikes. Basal spikelets 8-12 mm, subventricose, urceolate, with 2 fertile florets and 2-3 sterile florets; apical spikelets 4-5 mm, typically with 1 sterile floret, although cultivated forms may have 1 fertile floret and 1-2 sterile florets. Glumes of fertile spikelets 7-10 mm, usually velutinous, sometimes scabrous, apices with (2)3 awns, awns 2-5.5 cm; lemmas 2-awned, awns 0.5-4 cm, with 1 lateral tooth, the tooth sometimes reduced to a shoulder. Caryopses 5-7 mm, falling free of the lemmas and paleas. Haplomes UM, UMN. 2n = 28, 48.

Aegilops neglecta is native around the Mediterranean and in western Asia. It has been collected in Arlington County, Virginia, but is not established in the Flora region.