2. Raphanus sativus Linnaeus, Sp. Pl. 2: 669. 1753.
Annuals or biennials, roots often fleshy in cultivated forms; often sparsely scabrous or hispid, sometimes glabrous. Stems often simple from base, (1-)4-13 dm. Basal leaves: petiole 1-30 cm; blade oblong, obovate, oblanceolate, or spatulate in outline, lyrate or pinnatisect, sometimes undivided, 2-60 cm × 10-200 mm, margins dentate, apex obtuse or acute; lobes 1-12 each side, oblong or ovate, to 10 cm × 50 mm. Cauline leaves (distal) subsessile; blade often undivided. Fruiting pedicels spreading to ascending, 5-40 mm. Flowers: sepals 5.5-10 × 1-2 mm, glabrous or sparsely pubescent; petals usually purple or pink, sometimes white (veins often darker), 15-25 × 3-8 mm, claw to 14 mm; filaments 5-12 mm; anthers 1.5-2 mm. Fruits usually fusiform or lanceolate, sometimes ovoid or cylindrical; valvular segment 1-3.5 mm; terminal segment (1-)3-15(-25) cm × (5-)7-13(-15) mm, smooth or, rarely, slightly constricted between seeds, not ribbed, beak narrowly to broadly conical to linear; style 10-40 mm. Seeds globose or ovoid, 2.5-4 mm diam. 2n = 18.
Flowering May-Jul. Roadsides, disturbed areas, waste places, cultivated fields, gardens, orchards; 0-1000 m; introduced; B.C., Man., N.B., Nfld. and Labr., N.S., Ont., P.E.I., Que., Sask.; Ala., Alaska, Ariz., Ark., Calif., Colo., Conn., Del., D.C., Fla., Ga., Idaho, Ill., Ind., Iowa, Kans., Ky., La., Maine, Md., Mass., Mich., Minn., Miss., Mo., Mont., Nebr., Nev., N.H., N.J., N.Mex., N.Y., N.C., N.Dak., Ohio, Okla., Oreg., Pa., R.I., S.C., S.Dak., Tenn., Tex., Utah, Vt., Va., Wash., W.Va., Wis., Wyo.; Europe; Asia; introduced also in Mexico, Bermuda, South America, Africa, Atlantic Islands, Australia.
Raphanus sativus is an important crop plant that is cultivated and/or weedy in most temperate regions worldwide. It is unknown as a wild plant, but suggested to be derived from R. raphanistrum subsp. landra, which is endemic to the Mediterranean region (L. J. Lewis-Jones et al. 1982).