Weed Seed: Bromus arvensis (Field brome)

Family

Poaceae

Common Name

Field brome

Regulation

Secondary Noxious, Class 3 in the Canadian Weed Seeds Order, 2016 under the Seeds Act.

Distribution

Canadian: Occurs in ON (Brouillet et al. 2016Footnote 1); previously reported in BC and QC but currently excluded from the floras (Marie-Victorin 1995Footnote 2, Brouillet et al. 2016Footnote 1, Klinkenberg 2013Footnote 3).

Worldwide: Native to southern and south-central Europe and temperate Asia, and widely naturalized further north in Europe and in other temperate regions of the world (Tutin et al. 1980Footnote 4, Barkworth et al. 2007Footnote 5, USDA-ARS 2016Footnote 6). In the United States it occurs in several states, particularly on the east coast (Barkworth et al. 2007Footnote 5).

Duration of life cycle

Annual

Seed or fruit type

Floret

Identification features

Size

  • Floret length: 7.0 - 9.0 mm
  • Floret width: 1.0 - 1.5 mm
  • Awn length: 6.0 - 11.0 mm

Shape

  • Long oval-shaped floret with a flared top and extended lemma sides

Surface Texture

  • Lemma is papery and usually glabrous, can be scabrous on the upper half; margins often with hyaline margins

Colour

  • Floret is straw yellow

Other Features

  • Palea teeth longer than 1.0 mm.
  • Awn does not bend away from the lemma.

Habitat and Crop Association

Roadsides, fields, forest margins and waste places (Barkworth et al. 2007Footnote 5). A weed of arable land in Europe, notably in winter cereals (Tutin et al. 1980Footnote 4). Adapted to the corn-belt region and eastwards in the United States (Williams et al. 2011Footnote 7) and sometimes grown for erosion control or as a cover crop (soil improver) (Wiersema and Leon 1999Footnote 8).

General Information

Field brome was introduced to North America as a cover crop in the 1920s, and now occurs in several U.S. states. In Canada it has persisted as a weed in experimental field plots at the University of Guelph since 1933. Dore and McNeill (1980Footnote 9) noted that "this versatile and early maturing annual would be difficult to control if it became widely established".

Similar species

Japanese Brome (Bromus japonicus)

  • Japanese brome has a similar size, oval shape, straw colour and extended lemma sides as field brome.
  • Japanese brome's awn is up to 3.0 mm shorter than field brome and bends away from the lemma. The lemma sides tend to extend further past the grain than field brome. Japanese brome has hairs on the upper half of the lemma, while field brome usually has glabrous lemmas.

Photos

Field brome (Bromus arvensis) florets
Field brome (Bromus arvensis) florets
Field brome (Bromus arvensis) floret
Field brome (Bromus arvensis) floret
Field brome (Bromus arvensis) floret, palea teeth
Field brome (Bromus arvensis) palea teeth
Field brome (Bromus arvensis) extended lemma sides
Field brome (Bromus arvensis) extended lemma sides

Similar species

Similar species: Japanese brome (Bromus japonicus) florets
Similar species: Japanese brome (Bromus japonicus) florets
Similar species: Japanese brome (Bromus japonicus) floret, palea teeth
Similar species: Japanese brome (Bromus japonicus) palea (close-up)
Date modified: