1.
Raphanus raphanistrum
Linnaeus, Sp. Pl. 1: 669. 1753.
Wild-radish, jointed charlock or radish or wild-radish
Annuals,
roots not fleshy; sparsely to densely pubescent.
Stems
usually simple from base, (2-)3-8 dm, (retrorsely hispid).
Basal leaves:
petiole 1-6 cm; blade oblong, obovate, or oblanceolate in outline, lyrate or pinnatifid, sometimes undivided, 3-15(-22) cm × 10-50 mm, margins dentate, apex obtuse or acute; lobes 1-4 each side, oblong or ovate, to 4 cm × 20 mm (smaller than terminal).
Cauline leaves
(distal) subsessile; blade often undivided.
Fruiting pedicels
divaricate or ascending, 7-25 mm, (straight).
Flowers:
sepals 7-11 × 1-2 mm, sparsely pubescent; petals yellow or creamy white (veins dark brown or purple), 15-25 × 4-7 mm, claw to 15 mm; filaments (slender), 7-12 mm; anthers 2-2.5 mm.
Fruits
cylindrical or narrowly lanceolate; valvular segment 1-1.5 mm; terminal segment (1.5-) 2-11(-14) cm × (2.5-)3-8(-11) mm, (base rounded), strongly constricted between seeds (usually breaking), strongly ribbed, beak narrowly conical; style 10-50 mm.
Seeds
(reddish brown or dark brown to black), oblong or ovoid, 2.5-3.5 × 1.8-2.5 mm.
2
n
= 18.
Flowering May-Jul. Disturbed waste places, cultivated fields, roadsides, orchards, hill slopes; 0-800 m; introduced; Greenland; St. Pierre and Miquelon; Alta., 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, Central America, South America, Africa, Atlantic Islands, Australia.
North American representatives of
Raphanus raphanistrum
are referable to subsp.
raphanistrum
. Four other subspecies are restricted to Europe.
