Cow vetch, arveja silvestre

Cow Vetch is similar to a pea in growth habit, sending out noose-like tendrils from the tips of its leaves when it contacts another plant and securely fastens itself. An individual plant may reach a length (or height) of 2 m and its taproot may extend up to 1 m.
The leaves are 3–8 cm long, pinnate, with 8–12 pairs of leaflets, each leaflet 5-10 mm long.
The plant flowers in one-sided racemes of cascading pea-flower shaped purple to violet flowers from the leaf axil during its late spring to late summer flowering period.
The seed pods are 2 cm long, and like the flowers, resemble those of a very small pea. The tiny seeds within are ripe when the pods have turned black. Unripened seeds are swollen and have a green tint to them, but they unswell when they become ripe. The seed pods vary from light brown to dark brown with black spots.