Lathyrus sylvestris

Herbs perennial, from rhizome, glabrous. Stems broadly winged, sprawling or climbing, basally branched 1–3 times, 6–20 dm. Leaves 2–4 cm, rachises winged; tendrils well developed, branched; stipules linear, 10–30 × 1–3 mm, less than 1/2 width of stem, much smaller than leaflets; leaflets 2, blades linear, 20–150 × 4–24 mm, surfaces glabrous. Inflorescences 3–10-flowered, 9–27 cm. Flowers 12–17 mm; calyx lobes equal, lateral lobes deltate, usually shorter than tube; corolla red-purple, banner erect, blade longer than claw, wings equal to keel; ovary glandular-pubescent, style rotated 90° from ovary axis. Legumes 30–75 × 5–10 mm. 2n = 14.

Phenology: Flowering May–Aug.
Habitat: Roadsides, fencerows, waste ground.
Elevation: 0–1000 m.

Introduced; B.C., N.B., N.S., Ont., P.E.I., Que., Ala., Ark., Calif., Colo., Conn., Ga., Idaho, Ind., Ky., Mass., Mich., Minn., Miss., Mo., Mont., N.H., N.Y., Oreg., Pa., R.I., S.C., Utah, Vt., Va., Wash., W.Va., Wis., Wyo., Europe, introduced also in Mexico (Nuevo León), Pacific Islands (New Zealand).

Discussion

Lathyrus sylvestris is similar to L. latifolius and intermediate populations are known to occur in Europe (M. Valero 1991). In North America, L. sylvestris is distinguished by its distinctly narrower stipules.

Selected References

None.

Lower Taxa