Bromus diandrus Roth

Great Brome

Bot. Abh. Beobacht. 44 (1787) APNI

Taxonomic status:Accepted

Occurrence status:Present

Establishment means:Naturalised

Tufted annual, culms erect, to 80 cm high. Leaves with soft, spreading hairs; blade flat or loosely folded, to 15 cm long and 10 mm wide, lightly scabrous; ligule glabrous, torn at apex, 2–4 mm long. Inflorescence a loose panicle, to 15 cm long (excluding awns), branches initially sub-erect, usually drooping at maturity, the longest not or barely longer than the spikelets. Spikelets 4–10-flowered, oblong, 40–60 mm long (excluding awns), florets separating toward maturity; lower glume 1-nerved, 13–20 mm long, upper glume 3-nerved, 20–27 mm long; lemma 20–30 mm long, excluding awn, dorsally rounded, strongly scabrous, with 2 membranous apical lobes 4–7 mm long; awn 35–60 mm long. Flowers Sep.–Nov.

*Brid, *CVU, *DunT, *EGL, *EGU, *GipP, *Glep, *Gold, *GGr, *HNF, *HSF, *LoM, *MuF, *MuM, *MSB, *NIS, *OtP, *OtR, *RobP, *SnM, *Strz, *VAlp, *VRiv, *VVP, *WaP, *WPro, *Wim. Naturalised in all States, widely in temperate countries. Indigenous to the Mediterranean region and south-west Europe. Occurs throughout Victoria on disturbed soil (particularly roadsides) and a common crop weed in the north and west of the State.

The name Bromus rigidus Roth. has been applied to specimens collected from Walpeup in the Mallee having an erect, more compact inflorescence with the longest panicle branches mostly less than 15 mm. Other differences are attributed to this taxon, e.g. elliptical abscission scar on the callus (cf. circular for B. diandrus), but these have all been demonstrated as being variables within a continuum having 'typical' B. diandrus and B. rigidus as the end points.

Source: Walsh, N.G. (1994). Poaceae. In: Walsh, N.G.; Entwisle, T.J. (eds), Flora of Victoria Vol. 2, Ferns and Allied Plants, Conifers and Monocotyledons. Inkata Press, Melbourne.
Updated by: Val Stajsic, 2017-12-18
Hero image
Distribution map
life Life
kingdom Plantae
phylum Tracheophyta
superorder Lilianae
order Poales
family Poaceae
genus Bromus
Higher taxa


Source: AVH (2014). Australia's Virtual Herbarium, Council of Heads of Australasian Herbaria, <>. Find Bromus diandrus in AVH ; Victorian Biodiversity Atlas, © The State of Victoria, Department of Environment and Primary Industries (published Dec. 2014) Find Bromus diandrus in Victorian Biodiversity Atlas
  Bioregion Occurrence status Establishment means
Lowan Mallee present naturalised
Murray Mallee present naturalised
Wimmera present naturalised
Glenelg Plain present naturalised
Bridgewater present naturalised
Victorian Volcanic Plain present naturalised
Victorian Riverina present naturalised
Murray Scroll Belt present introduced
Robinvale Plains present naturalised
Murray Fans present naturalised
Gippsland Plain present naturalised
Otway Plain present naturalised
Warrnambool Plain present naturalised
Goldfields present naturalised
Central Victorian Uplands present naturalised
Greater Grampians present naturalised
Dundas Tablelands present naturalised
Northern Inland Slopes present naturalised
East Gippsland Lowlands present naturalised
East Gippsland Uplands present naturalised
Wilsons Promontory present naturalised
Highlands-Southern Fall present naturalised
Highlands-Northern Fall present naturalised
Otway Ranges present naturalised
Strzelecki Ranges present naturalised
Victorian Alps present naturalised
Snowy Mountains present naturalised

State distribution

Distribution map
Western Australia
Northern Territory
South Australia
New South Wales
Australian Capital Territory