Weed Seed: Pueraria montana (Kudzu)

Invasive Plant - Kudzu (Pueraria montana)

Family

Fabaceae

Common name

Kudzu

Regulation

Prohibited Noxious, Class 1 in the Canadian Weed Seeds Order, 2016 under the Seeds Act. All imported and domestic seed must be free of Prohibited Noxious weed seeds.

Listed on the List of Pests Regulated by Canada established under the Plant Protection Act.

Distribution

Canadian: One known population in southern ON under official control.

Worldwide: Native to eastern and southeastern Asia and introduced to southern Australia, South America, South Africa, New Zealand, central and eastern Europe and the United States (Lindgren et al. 2013^Footnote 1). There are severe infestations in the southeastern United States (CFIA 2014^Footnote 2).

Duration of life cycle

Perennial

Seed or fruit type

Seed

Identification features

Size

• Seed length: 3.1 - 5.0 mm
• Seed width: 2.5 - 3.5 mm
• Seed thickness: 2.0 mm

Shape

• Oval or D-shaped seed; compressed

Surface texture

• Seed smooth with a satiny sheen

Colour

• Seed usually reddish-brown or brown with black mottles; some seeds are a uniform colour

Other features

• Pale ring of tissue around hilum, located in the middle of narrow edge

Habitat and crop association

Abandoned fields and field edges, grasslands, pastures, natural forests, plantations, fencerows, roadsides, riverbanks and urban areas (CFIA 2012^Footnote 3, 2014^Footnote 2).

General information

Kudzu was planted as a soil stabilizer in the 1930s and 40s in the southeastern United States, where it persists today (CABI 2016^Footnote 4). In China and Japan, it is cultivated for forage, starch, food and medicine (CABI 2016^Footnote 4).

In recent years it has also been considered for biofuel use (Sage et al. 2009^Footnote 5). In its native range, kudzu grows best in areas with mild winters, hot summers and at least 100 cm of annual precipitation (CABI 2016^Footnote 4). It is known for its rapid vegetative growth and for quickly overwhelming native species (Forseth Jr. and Innis 2004^Footnote 6).

Similar species

Sainfoin (Onobrychis viciifolia)

• Similar size, D- shape, reddish-brown colour and raised tissue around hilum.
• Sainfoin seeds do not have mottles and the raised hilum tissue is thin.
• The single-seeded legume is often shed with the seed inside, while kudzu's legume is many-seeded and splits at maturity.

Photos

Similar species