Weed Seed: Linaria genistifolia (Broomleaf toadflax)

Family

Plantaginaceae

Common Name

Broomleaf toadflax

Regulation

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

Distribution

Canadian: Absent from Canada (Brouillet et al. 2016^Footnote 1).

Worldwide: Native to central and eastern Europe and temperate Asia (USDA-ARS 2016^Footnote 2). Introduced in France, Germany, Norway, and the United States, where it is present in Oregon, Minnesota, and some of the northeastern states (CABI 2016^Footnote 3).

Duration of life cycle

Perennial

Seed or fruit type

Seed

Identification features

Size

Seed length: 0.6 - 0.8 mm
Seed width: 0.4 - 0.5 mm

Shape

Seed blocky, often with one tapered end

Surface Texture

Seed covered in ridges that form a wavy-wrinkled pattern

Colour

Seed black with a bluish or silver sheen, immature seeds are greyish

Other Features

The seed edges are reticulated and winged, approximately 0.2 mm wide

Habitat and Crop Association

Pastures, roads and disturbed areas (Darbyshire 2003^Footnote 4).

Similar species

Dalmatian toadflax (Linaria dalmatica)

Dalmatian toadflax seeds are a similar size, blackish colour, rough surface and sharp winged edges as broomleaf toadflax.
The shape tends to be more blocky without one tapered end and the winged edges do not have a strong microscopic pattern compared to broomleaf toadflax.

Striped toadflax (Linaria repens)

Striped toadflax seeds are a similar size, dark colour and rough surface as broomleaf toadflax.
Striped toadflax seeds lack a winged edge and have a dull brownish surface compared to broomleaf toadflax.