False Brome

Brachypodium distachyon (L.) P. Beauv.

Synonyms - Bromus distachyos, Trachynia distachya.

Family: - Poaceae.

Names:

Brachypodium is from the Greek brachys meaning short and podion meaning a little foot and refers to the very short stalks on the spikelets.

False Brome because it resembles Brome grasses but is from a different genus.

Summary:

Small annual grass with leaves that are rough to touch and bent stems. 100-500mm tall with short bristly seed heads.

Description:

Cotyledons:

One.

Leaves:

Blade - Rough to touch. Short, 20-120 x 2-6mm. Flat. Lance shaped. Hairy on the upper side, under side and margins. Blue green with a waxy bloom (glaucous).

Ligule - 1mm long. Membranous. Densely hairy.

Auricles - None.

Sheath - May have some hairs on the margins.

Stems:

Usually bent at the nodes. 100-500 mm tall. Hairy nodes. Tufted. Usually erect, occasionally branched,

Flower head:

Erect, spike like racemes at end of stems with groups of 1-6 spikelets arranged alternately along the stem. Slightly flattened. 20-100 mm long. Held well above the leaves.

Flowers:

Spikelets - 20-50 mm long by 5-6 mm wide. Stalked, but often look like they have no stalk. Stiffly erect. Become flattened with maturity.

Florets - 7-15, bisexual.

Glumes - Firm, strongly ribbed. Unequal lengths. First (lower) glume 5 nerved, translucent edges, 5.5-7 mm long. Second glume 7-9 nerved, 7-8mm long. Translucent edges. Hairless except on edges.

Palea - Broad, rounded tip. 8-10mm long. Rigid hairs on the 2 nerves or keels.

Lemma - Stiff, leathery, rounded on the back. Initially overlapping. 7-10 mm long, 5-7 obvious nerves. Sparse, narrowly conical hairs on the upper half, hairy on the lower half, usually hairy on the margins and a few hairs on the back. Has a straight terminal rough awn (6-20 mm long) that is longer than the lemma (rarely awnless).

Stamens -

Anthers -

Disarticulates above the glumes and between the florets.

Fruit:

Seeds:

Roots:

Fibrous.

Key Characters:

Biology:

Life cycle:

Annual. Flowers August to January.

Physiology:

Reproduction:

Flowering times:

August to November in SA.

November to January in WA.

Seed Biology and Germination:

Vegetative Propagules:

None.

Hybrids:

None.

Allelopathy:

Population Dynamics and Dispersal:

Origin and History:

Europe, Asia, Mediterranean.

Distribution:

ACT, NSW, SA, TAS, VIC, WA.

Habitats:

Climate:

Mediterranean, temperate.

Soil:

Plant Associations:

Significance:

Beneficial:

Detrimental:

Weed of rotational crops and disturbed areas.

Toxicity:

None reported.

Legislation:

None.

Management and Control:

Thresholds:

Eradication strategies:

Herbicide resistance:

Biological Control:

Related plants:

None.

Plants of similar appearance:

False brome intermediate in structure between Common Wheatgrass and Brome Grass.

Brome grasses (Bromus spp.)have spikelets on relatively long stalks.

Common Wheatgrass (Agropyron scabrum) has spikelets without stalks.

False Brome has spikelets with very short stalks.

References:

Black, J.M. (1978). Flora of South Australia. (Government Printer, Adelaide, South Australia). P135. Diagram.

Ciba Geigy (1981) Grass Weeds 2. CIBA GEIGY Ltd, Basle, Switzerland. P132. Diagrams.

Lamp, C. and Collet, F. (1990). A Field Guide to Weeds in Australia. (Inkata Press, Melbourne). p???.

Lazarides, M. and Hince, B. (1993). CSIRO handbook of economic plants of Australia. (CSIRO, Melbourne). 192.1.

Marchant, N.G., Wheeler, J.R., Rye, B.L., Bennett, E.M., Lander, N.S. and Macfarlane, T.D. (1987). Flora of the Perth Region. (Western Australian Herbarium, Department of Agriculture, Western Australia). P996.

Paterson, J.G. (1977). Grasses in South Western Australia. (Western Australian Department of Agriculture Bulletin 4007). P30. Diagram.

Acknowledgments:

Collated by HerbiGuide. Phone 08 98444064 or www.herbiguide.com.au for more information.