Weed Seed: Lepidium chalepense (Lens-pod hoary cress)

Family

Brassicaceae

Synonyms

Cardaria chalepensis

Common Name

Lens-pod hoary cress

Regulation

Primary Noxious, Class 2 in the Canadian Weed Seeds Order, 2016 under the Seeds Act.

Distribution

Canadian: Occurs in AB, BC, MB, ON, SK (Brouillet et al. 2016Footnote 1).

Worldwide: Native to the Middle East and China and introduced in North America and Argentina (USDA-ARS 2016Footnote 2). In the United States it occurs in the west (Francis and Warwick 2008Footnote 3).

Duration of life cycle

Perennial

Seed or fruit type

Seed

Identification features

Size

  • Seed length: 2.0 - 2.8 mm
  • Seed width: 1.5 - 2.0 mm
  • Seed thickness: 1.5 mm

Shape

  • Seed oval, compressed, the hilum area is flattened

Surface Texture

  • Seed granular

Colour

  • Seed reddish-brown

Other Features

  • Pods are globose, inflated, 2.5 - 6.0 mm long and 4.0 - 6.0 mm wide, usually hairy
  • The seed is ovate in cross section, often with a small furrow between the radicle and cotyledons

Habitat and Crop Association

Cultivated fields, old fields, grasslands, pastures, feed lots, riparian areas, ditches, roadsides, railway lines and disturbed areas (Darbyshire 2003Footnote 4, Zouhar 2004Footnote 5, Francis and Warwick 2008Footnote 3). A weed of alfalfa fields and pastures in Canada (Francis and Warwick 2008Footnote 3).

General Information

Contaminated alfalfa seed or horse feed was the probable cause of lens-pod hoary cress seed introduction into North America (Francis and Warwick 2008Footnote 3).

Similar species

Globe-pod hoary cress (Lepidium appelianum)

  • Globe-pod hoary cress seeds are a similar size, reddish-brown colour, rough surface and oval shape as lens-pod hoary cress.
  • Globe-pod hoary cress seeds are oval-shaped in cross-section due to a larger radicle than lens-pod hoary cress.

Heart-pod hoary cress (Lepidium draba subsp. draba)

  • Heart-pod hoary cress seeds are a similar size, roughened surface and oval shape as lens-pod hoary cress.
  • Heart-pod hoary cress seeds are darker brown with surface reticulation.

Photos

Lens-pod hoary cress (Lepidium chalepense) seeds and pod
Lens-pod hoary cress (Lepidium chalepense) seed
Lens-pod hoary cress (Lepidium chalepense) seed
Lens-pod hoary cress (Lepidium chalepense) seed
Lens-pod hoary cress (Lepidium chalepense) seed, close-up view of the hilum
Lens-pod hoary cress (Lepidium chalepense) seed, cross-section

Similar species

Similar species: Globe-pod hoary cress (Lepidium appelianum) seeds and pod
Similar species: Globe-pod hoary cress (Lepidium appelianum) seed
Similar species: Heart-pod hoary cress (Lepidium draba subsp. draba) pod and seeds
Similar species: Heart-pod hoary cress (Lepidium draba subsp. draba) seed
Similar species: Comparison of Lepidium spp. seed cross-sections