8. Trifolium dubium Sibthorp, Fl. Oxon. 231. 1794.
钝叶车轴草 dun ye che zhou cao
Annual herbs, glabrous to sparsely pubescent. Stems erect to decumbent, (5-)10-30(-40) cm. Leaves pinnately 3-foliolate; stipules obliquely ovate, 4-8 mm, base rounded, margins finely dentate, apex acute; petiole shorter than or equal to leaflets; terminal petiolule longer than lateral petioles; leaflets obovate, 5-10(-12) × 3-8 mm, veins 6-8 pairs, base cuneate, margins entire proximally, obscurely serrulate distally, apex rounded or emarginate. Flowers 5-15, in axillary heads; peduncle 0.5-3(-4) cm, pubescent; pedicels less than 1 mm, after flowering pendulous. Calyx ca. 2 mm, veins 5. Corolla pale yellow, turning brown, 3-4 mm; standard narrowly boat-shaped, smooth, apex acute. Legume oblong, 1.5-2 mm, shortly beaked; stipe ca. 1 mm. Seed 1, pale brown, globose. Fl. and fr. Apr-Sep.
Cultivated, escaped, and naturalized. Jiangsu, Shaanxi, Taiwan [native to SW Asia and Europe].