8.
Sisymbrium officinale
(Linnaeus) Scopoli, Fl. Carniol. ed. 2. 2: 26. 1772.
Erysimum officinale
Linnaeus, Sp. Pl. 2: 660. 1753;
Sisymbrium officinale
var.
leiocarpum
de Candolle
Annuals;
glabrous or pubescent.
Stems
erect, branched distally, 2.5-7.5(-11) dm, usually sparsely to densely hirsute, (trichomes retrorse), rarely glabrate distally.
Basal leaves
usually rosulate; petiole (1-)2-7(-10) cm; blade broadly oblanceolate or oblong-obovate (in outline), (2-)3-10(-15) cm × (10-)20-50 (-80) mm, margins lyrate-pinnatifid, pinnatisect, or runcinate; lobes (2)3 or 4(5) on each side, oblong or lanceolate, smaller than terminal lobe, margins entire, dentate, or lobed, (terminal lobe suborbicular or deltate, margins dentate).
Cauline leaves
similar to basal; blade with lobe margins dentate or subentire.
Fruiting pedicels
erect, (appressed to rachis), stout, narrower than fruit, 1.5-3(-4) mm.
Flowers:
sepals erect, oblong-ovate, 2-2.5 × ca. 1 mm; petals spatulate, 2.5-4 × 1-2 mm, claw 1-2 mm; filaments (erect, yellowish), 2-3 mm; anthers ovate, 0.3-0.5 mm.
Fruits
(erect), subulate-linear, straight, slightly torulose or smooth, stout, (0.7-)1-1.4(-1.8) cm × 1-1.5 mm; valves glabrous or pubescent; ovules 10-20 per ovary; style (0.8-)1-1.5 (-2) mm; stigma slightly 2-lobed.
Seeds
1-1.3 × 0.5-0.6 mm.
2
n
= 14.
Flowering Apr-late Sep. Roadsides, fields, pastures, waste grounds, deserts; 0-2200 m; introduced; Alta., B.C., Man., N.B., Nfld. and Labr. (Nfld.), N.W.T., N.S., Ont., P.E.I., Que., Yukon; Ala., Alaska, Ark., Calif., Conn., Del., Fla., Ga., Idaho, Ill., Ind., Iowa, Kans., Ky., La., Maine, Md., Mass., Mich., Minn., Miss., Mo., Mont., N.H., N.J., N.Mex., N.Y., N.C., Ohio, Okla., Oreg., Pa., R.I., S.C., S.Dak., Tenn., Tex., Utah, Vt., Va., Wash., W.Va., Wis.; Europe; Asia; n Africa; introduced also in Central America, South America, Australia.
