Purple Vetch

Vicia benghalensis L.

Synonyms - Vicia atropurpurea

Family: - Fabaceae


Vicia is the Latin name for vetch.


Other Names:

Algerian Vetch

Popany Vetch



A hairy, annual or biennial vine with stems to 1 m long and clusters of 2-12, purple, pea type flowers, 10-20 mm long in early summer that produce hairy pods with a hooked tip.



Two. Non emergent and remain underground if buried. Round.

First leaves:

The first and second leaf have two pairs of narrowly spear shaped leaflets with a single short tendril at the end of the leaf. Later leaves have up to 9 pairs of leaflets.


Have a long, branched, twining tendril at the tip and 10-18 leaflets that are loosely paired but often not directly opposite each other.

Stipules - Small, 3-10 mm long with toothed or smooth edges.

Petiole -

Blade - Of leaflet is narrowly oval, 9-25 mm long by 1.5-6 mm wide. Tip pointed to rounded and has a small spine where the midrib extends beyond the leaflet. Sides convex. Base tapered.

Tendrils - slender and branched.


200-1000 mm long.

Flower head:

2-12 flowered raceme on a stalk arising from the leaf axils. Flowers on short stalks.


Red-purple pea type

Ovary -

Calyx - 5-11 mm long, lobed and has a large pouch near the base. Lobes parallel sided, different sizes, up to 7 mm long, lower lobe longer than the tube.

Petals - Red-purple and black at the tip. Standard 10-18 mm long. Limb narrowly egg shaped, Wings 9-15 mm long.

Stamens -

Anthers -


Brown pod, hooked at the tip, 23-40 mm long by 8-12 mm wide, on a short stalk, with 2-5 seeds. Hairy.


Round and black, with a white stripe (hilum). 4-5 mm diameter. Yellow flesh apparent when split or seed coat removed. Surface smooth and hairless.


Has nitrogen fixing nodules.

Key Characters:

Flowers in a 2-12 flowered pedunculate raceme

Calyx gibbous

Flowers 10-18 mm long.

Pod narrowly oblong to oblong with 1-5 seeds.


Life cycle:

Annual or biennial. Seeds germinate in autumn to winter and form a dense tangled mat of vines over winter. It flowers in spring and produces pods. The top growth normally dies with the onset of hot and dry conditions.


Has an association with Rhizobia in nodules in the roots which allows it to fix atmospheric nitrogen.


By seed.

Flowering times:

October to November in the Perth region.

Early summer in WA.

Seed Biology and Germination:

Vegetative Propagules:



Population Dynamics and Dispersal:

Spread by seed.

Origin and History:








Plant Associations:



Fodder, grain.


Weed of crops and disturbed areas.


Stock may suffer from grain poisoning on dense mature areas especially after rain.





Management and Control:

Grazing normally provides control.

Plant tall growing species in amenity areas.


Eradication strategies:

Prevent seed set for 5 years by grazing, mowing, pulling or applying herbicides.

Hand spray with 1 g of chlorsulfuron(700g/kg) plus 25 mL wetting agent in 10 L of water or boom spray with 20 g/ha chlorsulfuron(700g/kg) in autumn to early winter each year. Hand pull survivors in spring before seed set.

For small infestations and in grass dominant areas an annual application of 10 mL Tordon®75-D in 10 L water in early winter gives excellent control of existing plants and has residual activity to control seedlings.

In bushland, 200 g/ha Lontrel®750 or 50 g/ha Logran® applied in early winter provides reasonably selective control. For hand spraying use 25 mL wetting agent plus 4 g Lontrel®750 or 1 g Logran® in 10 L water. Repeat annually for several years.

Plant tall growing perennial species to reduce re-invasion.

Metsulfuron also provides good control but is less residual and less selective. It is relatively tolerant to glyphosate.

Herbicide resistance:

None reported.

Biological Control:

Related plants:

Broad Bean (Vicia faba var. major)

Common Vetch (Vicia sativa ssp. sativa) has leaves are divided like a feather into 3-10 pairs of small narrow leaflets, each 8-30 mm long. It has pink to purple pea flowers, each 10-20 mm long and either single or in few-flowered clusters. The seed pod is narrow, slightly flattened and 30-50 mm long.

Hairy Vetch (Vicia hirsuta) has an elongated inflorescence of several small flowers each only 2-3 mm long and small, 6-9 mm long hairy seed pods.

Horse Bean (Vicia faba var. equina)

Narbon Bean (Vicia narbonensis)

Narrow-leaved Vetch (Vicia sativa ssp. nigra)

Narrowleaf Vetch (Vicia sativa ssp. angustifolia)

Purple Vetch (Vicia benghalensis, Vicia atropurpurea)

Russian Vetch (Vicia villosa ssp.)

Slender Vetch (Vicia tetrasperma)

Spurred Vetch (Vicia monantha)

Tick Bean (Vicia faba var. minor)

Tufted Vetch (Vicia cracca)

Woollypod Vetch (Vicia villosa ssp. dasycarpa)

Vicia disperma

Vicia lathyroides

Plants of similar appearance:

Clover has trifoliate leaves


Pea has stipules about the same size as the leaflets

Lathyrus has a single pair of leaflets




Bodkin, F. (1986). Encyclopaedia Botanica. (Angus and Robertson, Australia).

Everist, S.L. (1974). Poisonous Plants of Australia. (Angus and Robertson, Sydney).

Harden, Gwen J. (1991). Flora of NSW. (Royal Botanic Gardens, Sydney). Volume . P448. Diagrams.

Hussey, B.M.J., Keighery, G.J., Cousens, R.D., Dodd, J. and Lloyd, S.G. (1997). Western Weeds. A guide to the weeds of Western Australia. (Plant Protection Society of Western Australia, Perth, Western Australia). P162. Photo.

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

Lazarides, M. and Cowley, K. and Hohnen, P. (1997). CSIRO handbook of Australian Weeds. (CSIRO, Melbourne). #1049.2.

Marchant et al (1987). Flora of the Perth Region. (Western Australian Herbarium, Department of Agriculture, Western Australia). P308.

Moerkerk, M.R. and Barnett, A.G. (1998). More Crop Weeds. R.G. and F.J. Richardson, Melbourne. P96. Diagrams. Photos.


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