American Vetch

Vicia americana

American Vetch (Vicia americana) is a native perennial vine of the pea family that climbs through grass and shrubs with curling tendrils at the tips of its leaves, and carries loose clusters of 3 to 9 purple pea flowers. In the Black Hills it blooms from late May into July, peaking in June, in open pine woods, aspen groves, meadows and prairie.

Free photos from other sources

American Vetch: Loose cluster of purple pea flowers among grass and leaves — American Vetch (Vicia americana). Jo Roberts, CC BY 4.0, resized. Get it at the source

American Vetch: Three purple pea flowers on a short stalk, close up against a dark background — American Vetch (Vicia americana). Brian Finzel, CC BY-SA 4.0, resized. Get it at the source

American Vetch: Leaf of paired oval leaflets ending in a curling tendril — American Vetch (Vicia americana). Brian Finzel, CC BY-SA 4.0, resized. Get it at the source

American Vetch: Low prairie plant with narrow leaflets and a few purple flowers — American Vetch (Vicia americana). Craig Martin, CC0 1.0. Get it at the source

American Vetch: Leaf base with small, sharp-toothed stipules — American Vetch (Vicia americana). Brian Dickerson, CC0 1.0. Get it at the source

American Vetch: Young green pod on a leafy stem — American Vetch (Vicia americana). Jo Roberts, CC BY 4.0, resized. Get it at the source

Quick facts
Family	Fabaceae · Pea
Status	Native perennial
Blooms	Late May into July, with a few into August
Height	30–100 cm (12–40 in)
Where	Open pine and aspen woods, forest edges, meadows, roadsides and mixed-grass prairie
Also called	Purple Vetch, Wild Vetch, American Purple Vetch, Stiffleaf Vetch, Wild Pea, tȟasúsu (Lakota)
Synonym	Vicia americana var. linearis, Vicia linearis, Vicia sparsifolia, Vicia caespitosa
Traditional use	Sitting Bull College's 1998 Culturally Important Plants of the Lakota says a poultice of the leaves was applied to spider bites and women used an infusion of the leaves as love medicine, and it notes the plant as excellent forage for grazing animals.

Roots, seeds & germination

Root: Creeping underground stems (rhizomes) lie shallow, about 1.5–5 cm (½–2 in) down, and a branched taproot can reach about 100 cm (40 in), which makes the plant drought-tolerant. Like most legumes it has root nodules with bacteria that take nitrogen from the air. The shallow rhizomes resprout after light to moderate fire.

Seed: Pods 2–3.5 cm (about 1–1½ in) long turn from green to reddish brown and split easily when ripe, holding two to several hard-coated, pea-like seeds about 3 mm long. Seeds ripen about a month after flowering.

Germination: Seed sprouts well without treatment: untreated seed germinated 85–87% in tests for a British Columbia seed manual, with the first seedlings after about two weeks. Scratching the seed coat speeds sprouting to 3–7 days but doesn't raise the final rate. USDA advises sowing in fall.

How do you identify American Vetch?

Each leaf has 8–16 paired leaflets and ends in a thin, curling tendril instead of a last leaflet. At the base of each leaf stalk is a pair of small, sharply toothed flaps (stipules) that often look star-like, a good check when the plant isn't in flower. The 3–9 pea flowers, 1.5–2.5 cm (⅝–1 in) long, sit in a loose cluster on a stalk shorter than the leaf and run from bluish to reddish purple, sometimes pink. Prairie plants are shorter and more upright, with narrow, stiff leaflets.

When does it bloom?

Late May into July, with a few into August.

Where does it grow?

Moist to fairly dry, open to partly shaded ground: ponderosa pine and aspen woods, forest edges, meadows, shrubby draws, roadsides and mixed-grass prairie. It tolerates shade and grows in every stage from fresh burns to mature forest. The 1986 Jewel Cave survey lists it as Wild Vetch, National Park Service lists record it at Wind Cave, Mount Rushmore and Devils Tower, and herbarium specimens come from all seven Black Hills counties, including Custer State Park.