Eruca sativa Miller, Gard. Dict., ed. 8, Eruca no. 1. 1768; Brassica eruca Linnaeus; E. cappadocica Reuter var. eriocarpa Boissier; E. lativalvis Boissier; E. sativa var. eriocarpa (Boissier) Post.

Herbs annual, (10-)20-80(-100) cm tall, glabrous or retrorsely hirsute or hispid. Stems erect, usually branched above. Basal leaves not rosulate, often withered by fruiting time; petiole (1-)2-5(-7) cm; leaf blade dentate, lyrate, pinnatifid, pinnatisect, or bipinnatisect, (2-)4-15(-20) × (1-)2-4(-6) cm; terminal lobe suborbicular or broadly ovate, margin dentate or entire; lateral lobes (2 or)3-9 on each side of midvein, oblong or oblong-ovate, margin pinnatifid, pinnatisect, dentate, or entire. Upper cauline leaves subsessile; leaf blade lobed or not. Fruiting pedicels 2-7(-10) mm, slightly thickened, erect or ascending, appressed or subappressed to rachis. Sepals often purplish, oblong, (6-)7-10(-12) × 1.5-2.2 mm, glabrous or hairy, deciduous, weakly cucullate or not. Petals yellow turning white, with dark brown or purplish veins, broadly obovate or spatulate, (1.2-)1.5-2(-2.6) cm × (4-)5-7(-9) mm, apex rounded; claw as long as sepals or slightly longer. Lateral filaments (5-)7-11 mm; median filaments (8-)10-13(-15) mm; anthers narrowly oblong, 2-3 mm. Fruit linear, oblong, or ellipsoid, (1.1-)1.5-3.5(-4) cm × (2.5-)3-5 mm, glabrous or retrorsely hispid or hirsute; valves (0.7-)1-2.5(-3.2) mm, with a prominent midvein; terminal segment ensiform, (4-)5-10(-11) mm, 5-veined, as long as or slightly shorter than valves. Seeds brown, globose or ovoid, 1.5-2.5 mm in diam. Fl. May-Jul, fr. Jun-Aug. 2n = 22*.

Eruca vesicaria subsp. vesicaria is endemic to Spain and NW Africa and is distinguished by having persistent, strongly cucullate sepals. Forms with retrorsely hirsute fruit were recognized in FRPS and some other provincial floras as Eruca sativa var. eriocarpa, but these always occur with glabrous forms in the same population and throughout the naturalized or native ranges of the species. Therefore, no infraspecific taxa merit recognition.

Widely cultivated in Asia for seed oil which is used as an illuminant, lubricant, and for pickling. The seed oil is one of the richest sources of erucic acid, which is important in industry. The young plants are medicinal and used as a stimulant, antiscorbutic, stomachic, and diuretic. The species is a naturalized weed worldwide, but it is extensively cultivated in Europe and North America as a salad plant.

Waste areas, fields, roadsides, slopes; near sea level to 3800 m. Gansu, Guangdong, Hebei, Heilongjiang, Jiangsu, Liaoning, Nei Mongol, Qinghai, Shaanxi, Shanxi, Sichuan, Xinjiang [Afghanistan, India, Kazakhstan, Kyrgyzstan, Mongolia, Pakistan, Russia, Tajikistan, Turkmenistan, Uzbekistan; NW Africa, SW Asia, Europe; naturalized elsewhere].