About Vicia nigricans Hook. & Arn.
Vicia nigricans Hook. & Arn. is a species of vetch commonly known as black vetch. It has a disjunct distribution, with its two subspecies separated by thousands of miles in range. The northern subspecies, Vicia nigricans ssp. gigantea (common name giant vetch), is native to western North America, ranging from Alaska to northern California. It grows in coastal habitats, moist inland habitats, and disturbed areas. The southern subspecies, Vicia nigricans ssp. nigricans, occurs in southern South America, specifically in Argentina and Chile. This vetch is a perennial herb that produces stout, hollow, ridged climbing stems that can reach up to two meters in length. It uses large branched tendrils to attach itself to objects and other plants for structural support. Its leaves are composed of 9 to 13 pairs of leaflets, which are either lance-shaped or elongated oval and can measure up to 4 centimeters in length. The inflorescence is a one-sided raceme holding up to 15 or 20 flowers. Flower corollas range in color from pale pink to dark reddish purple, and are sometimes yellowish to orange. Individual flowers are 1 to 2 centimeters long, with a calyx that is about half as long as the corolla. After flowering, the plant produces legume fruit pods that measure up to 4 centimeters long by 1.5 centimeters wide. The pods turn black as they dry.
