Common Vetch (Vicia sativa) — identification, habitat & look-alikes

Common vetch is a sprawling, pea-flowered vine with pink-to-purple blossoms set singly or in pairs along the stem, often seen in fields and along roadsides. Its seeds turn up at some of the earliest farming sites in the Near East. In the US it is an introduced plant, sown as a and forage and now widespread as a weed.

Appearance

Growth form: An annual vine with four-sided stems that scramble over or climb on other plants, roughly 1–5 ft (30–150 cm) long. In the Southeast it behaves as a winter annual, sprouting in fall.
Leaves: Compound leaves with 3–8 pairs of leaflets, ending in a branched tendril that grabs nearby plants. A dark purplish-brown nectar spot often shows on the underside of the at the leaf base.
Flowers: Pink to purple pea-shaped flowers (rarely white), ⅜ to over 1 in (1–2.5 cm) long, sit 1 or 2 together on very short stalks in the leaf axils. Bumblebees and other long-tongued bees pollinate them.
Flowering time: Blooms in spring in North Carolina, but July through September in Minnesota.
Fruit: Flat pods up to about 2 in (5 cm) long hold 4–12 round seeds and ripen light brown or black.

Look-alikes

Hairy vetchVicia villosa

Hairy vetch carries 10–40 flowers lined up on one side of a long-stalked spike and is covered in spreading hairs. Common vetch has only 1 or 2 nearly stalkless flowers per leaf axil.

Why they get mixed upBoth are purple-flowered, introduced vetches planted as cover or forage crops.

American vetchVicia americana

American vetch, a native wildflower, carries 2–9 flowers in loose clusters on a stalk, and its stipules have sharp teeth. Common vetch's flowers sit singly or in pairs right against the stem.

Why they get mixed upSimilar leaves and purple pea flowers on the same kind of vine.

Hairy tareVicia hirsuta

Hairy tare has tiny whitish or pale blue flowers only a few millimeters long, several to a stalk, and small hairy pods with about two seeds.

Why they get mixed upAnother weedy vetch with tendrils growing in the same spots.

Where it lives

Typical habitats: Fields
Meadows
Roadsides
Waste areas
Cropland
Range: Native to Europe, western Asia, and North Africa, and now naturalized almost worldwide. In the US it is an introduced plant that turns up as a weed of fields and roadsides in many states, including New England, the Southeast, and the Midwest.
Flowering: Flowers Jul–Sep
Flowers Jul–Sep

Cautions

Cautions: The seeds are listed as mildly poisonous, and livestock that eat too much vetch, especially with pods, can get colic or other stomach trouble.

Name and classification

About the name: Two forms are common in the US. Narrow-leaved vetch (subsp. nigra, once called Vicia angustifolia) has smaller flowers, slim leaflets, and pods that turn black; spring vetch (subsp. sativa) has bigger flowers, broader leaflets, and brown pods. Leaflet shape varies even on one plant, so check several leaves.

Conservation

IUCN Red List: LCLeast ConcernLow risk of extinction

Culture and stories

Culture and stories: Charred seeds turn up at early Neolithic sites in the Near East and Europe and at Predynastic sites in Egypt, though clear proof of deliberate farming dates to Roman times.