Leon E. Pavlick† and Laurel K. Anderton

Plants perennial, annual, or biennial; usually cespitose, sometimes rhizomatous. Culms 5–190 cm. Sheaths closed to near the top, usually pubescent; auriclesusually absent; ligules membranous, to 6 mm, usually erose or lacerate; blades generally flat, rarely involute. Inflorescences panicles, sometimes racemose, erect or nodding, open or dense, occasionally 1-sided; branches usually ascending to spreading, sometimes reflexed or drooping. Spikelets 5–70 mm, terete to laterally compressed, with 3–30 florets; disarticulation above the glumes, beneath the florets. Glumes unequal, usually shorter than the adjacent lemmas, always shorter than the spikelets, glabrous or pubescent, usually acute, rarely mucronate; lower glumes 1–7(9)-veined; upper glumes 3–9(11)-veined; lemmas 5–13-veined, rounded to keeled, glabrous or pubescent, apices entire, emarginate, or toothed, usually terminally or subterminally awned, sometimes with 3 awns or unawned; paleas usually shorter than the lemmas, ciliate on the keels, adnate to the caryopses; anthers (2)3. x = 7. Name from the Greek bromos, an ancient name for ‘oats’, which was based on broma, ‘food’.

Bromus grows in temperate and cool regions, and is estimated to include 100–400 species, depending on differences in how the species are interpreted. Of the 52 species in the Flora region, 28 are native and 24 are introduced. The native perennial species provide considerable forage for grazing animals, with some species being cultivated for this purpose. The introduced species, all but three of which are annuals, range from sporadic introductions to well-established members of the region’s flora. Many are weedy and occupy disturbed sites. Some are used for hay; others have sharp, pointed florets and long, rough awns that can injure grazing animals.

This treatment is based on one submitted by Pavlick, who died before it could be reviewed and edited. It has been substantially revised by Anderton to meet the requirements for publication in this volume. The majority of Pavlick’s taxonomic concepts are retained, despite the necessity for overlap in many key leads; time constraints prevented a thorough investigation of problematic taxa. We thank Hildemar Scholz of the Botanic Garden and Botanical Museum Berlin-Dahlem, Free University Berlin, for his assistance in providing accurately identified specimens of the weedy European species for use in preparing the illustrations, as well as helpful keys and descriptions.

In the key and descriptions, the distances from the bases of the subterminal lemma awns to the lemma apices are measured on the most distal florets in a spikelet.

The references included in the FNA treatment can be found under the "References" tab.

T.A. Cope (1995) Bromus. Flora of Somalia 4: 157

Plants annual or perennial. Leaves: sheaths with the margins united for most of their length, usually hairy. Panicles open or contracted. Spikelets cuneate to ovate, breaking up below each floret; lemmas with a single awn.

The number of species recognized in Bromus varies considerably, from 150 to 200 or more. One species, Bromus leptoclados, has been found in Somaliland. The Flora of Somalia does not report any from Somalia.

Global distribution of Bromus

Note: GBIF records include introduced and cultivated plants. Consequently, the distribution shown often differs from statements about a taxon's native distribution.

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