Lotus pedunculatus (formerly Lotus uliginosus), the big trefoil, greater bird's-foot-trefoil or marsh bird's-foot trefoil, is a member of the pea family (Fabaceae). It is a herbaceous perennial growing throughout Europe in damp, open locations. As one common name suggests, it is a larger plant than related Lotus species, growing 20–80 cm (8–30 in) tall, with leaflets 10–25 mm (0.4–1 in) long and 10–20 mm (0.4–0.8 in) broad. Five to twelve golden-yellow flowers 10–18 mm (0.4–0.7 in) long are borne in an umbel at the tip of the upright stem.