Slender vetch: A hairless to sparsely hairy annual. The leaves are compound with 8-12 narrowly oblong leaflets, each 10-25 mm long. Tendrils at leaf tips. Stems are slender, 30-70 cm tall. Flowers are bluish and pea-shaped, 5-6 mm long. There are 2-3 flowers per flowering stalk, arising from the leaf axils. Flowers all summer. Hairless pods to 1.5 cm contain 3-5 seeds. Spreads by rhizomes as well as seeds.