Kingdom: Plantae
(unranked): Angiosperms
(unranked): Eudicots
(unranked): Rosids
Order: Fabales
Family: Fabaceae
Subfamily: Faboideae
Tribe: Vicieae
Genus: Vicia
Species: V. sativa
Binomial name: Vicia sativa
Synonyms: Vicia angustifolia, Vicia angustifolia, Vicia cordata, Vicia cuneata, Vicia cuneata, Vicia heterophylla, Vicia segetalis.
Common names: Common vetch, Vetch, Narrow-leaved vetch.

Vicia sativa is a variable sprawling nitrogen-fixing leguminous plant that is a member of the pea family Fabaceae. It is a native of Europe, West Asia and North Africa. Vicia sativa consists of a great number of varieties, each differing from each other in development, flowering time, the colour of flower and seed, etc. In New Zealand, it is classed as a weed. This common weed forms large mats of vegetation in gardens, waste areas, roadsides, coastal areas and forest margins.

Vicia sativa is slender to stout scrambling or tufted annual, which has hollow, four-sided, hairless to sparsely hairy stems which can reach 80 cm in length.
The leaves are stipulate, alternate and compound, each made up of 3 to 8 opposite pairs of linear, lance-shaped, oblong, or wedge-shaped needle-tipped leaflets up to 3.5 centimetres long. The compound leaves end in a sensitive thread called a tendril. These tendrils wind themselves around any object they come in contact with and thus help to support the weak stems of the plant.
The flowers occur solitary or in pairs in the leaf axils. They have very short or no stalks. The flower corolla is 1 to 3 centimetres in length and is usually purple or pink in colour. Some forms are white or yellow.
Late in the season after the flowers drop, seed pods form. They are a 30-70mm long legume pod with 5-12 seeds that are round and flattened, usually black in most varieties but grey, white or reddish in others. The pods are first green and hairy but become smooth on maturity and turn a brown or black colour.
In the past, it has been grown as an animal fodder.

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Vicia sativa growing roadside.
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An opening flower.
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The rear of the flower.
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Seed pods
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The underside of the leaflets.
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Thanks to Wikipedia for text and information:

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