Plants stoloniferous. Aerial stems ± scapiform. Leaf blades 5-30+ × 5-30+ mm, margins often with 1(-2), ± retrorse teeth near bases. Peduncles (1-)5-15+ cm. Involucres 8-10 mm. Cypselae 6 mm; pappi 4-7 mm. 2n = 16, 24. Flowering Jun-Aug. Disturbed sites; 0-100 m; introduced; Del., N.J., N.Y., Pa.; Asia (Japan). The combination Lactuca stolonifera has been mistakenly attributed to '(A. Gray) Bentham & Hooker f.'