Vicia cracca L. (tufted vetch, Canada pea, bird vetch)

Pl. 411 b; Map 1825

Plants perennial, with rhizomes. Stems 40–150 cm long, trailing or climbing, sparsely or more commonly moderately to densely pubescent with short, fine, curved hairs. Leaves with 14–22 leaflets, the petiole absent or to 3 mm long, the tendrils branched or rarely a few of them unbranched. Stipules 2–5 mm long, lacking a glandular spot, with a narrowly triangular basal lobe (rarely unlobed), the margins otherwise entire. Leaflets 10–25 mm long, 2–5 mm wide, those of the lower leaves not strongly reduced, linear to narrowly oblong, narrowly elliptic, or the smallest ones sometimes elliptic, rounded or angled at the base, variously rounded to bluntly or sharply pointed or occasionally nearly truncate at the tip, the midvein often extended as a minute, sharp point at the very tip, the surfaces finely hairy. Inflorescences racemes, usually relatively dense, the stalk 2–5 cm long, the flowers (10–)15–30, each with a stalk 1–3 mm long. Calyces finely hairy, often somewhat purplish-tinged, the tube 1.8–2.8 mm long, the base somewhat oblique and sometimes slightly pouched on 1 side, the attachment appearing basal but off-center, the lobes 0.5–2.5 mm long, unequal, the upper pair broadly triangular, the lowermost narrowly triangular to lanceolate-triangular, 2–3 times as long as the upper lobes. Corollas 9–13(–18) mm long, blue to bluish purple, rarely lilac or white, the wings and keel occasionally lighter than the banner, the banner bent or curved upward at or above the midpoint, strongly curved around the wings and keel. Stamens with the fused portion 5–6 mm long, the free portion 1–2 mm long. Style encircled by a dense ring of short hairs toward the tip. Fruits 18–30 mm long, 6–8 mm wide, short-stalked, glabrous, light brown to grayish brown at maturity, 4–9-seeded. Seeds 2.5–3.0 mm long, yellowish brown to reddish brown or dark grayish brown, occasionally nearly black, often with darker mottling, more or less circular in outline, not or only slightly flattened, the attachment scar not raised, yellowish brown to brown with a lighter border, extending up to 1/3 the circumference of the seed. 2n=12, 14, 21, 22, 28. July–August.

Introduced, uncommon, known thus far only from the city of St. Louis (native of Europe, Asia; introduced widely in the U.S. [including Alaska, Hawaii], Canada, Greenland, Mexico). Railroads.

Steyermark (1963) excluded this species from the Missouri flora, stating that specimens attributed to this species examined by him were misdetermined collections of V. villosa. However, Mühlenbach (1979) confirmed the presence of the species from the St. Louis railyards.