Linnaeus, Sp. Pl. 2: 666. 1753.
Canola, oilseed rape, rape, rapeseed, rutabaga, swede, swede rape, Swedish turnip
Annuals or biennials;
(taproot slender or swollen); (glaucous), glabrous, glabrescent, or pubes-cent, (trichomes coarse).
branched distally, 3-13 dm.
(rosulate when biennial); petiole (often winged), to 15 cm; blade lyrate-pinnatifid, ± pinnately lobed, 5-25(-40) cm × 20-70(-100) mm, lobes 0-6 each side, (smaller than terminal), surfaces (glaucous), glabrous or sparsely hairy when immature, glabrescent, or, rarely, pubescent.
(middle and distal) sessile; blade base auriculate or amplexicaul, (margins entire).
not paniculately branched, (buds overtopping or equal to open flowers).
spreading to ascending (slender), 1-3 cm.
sepals (5-)6-10 × 1.5-2.5 mm; petals golden or creamy to pale yellow, broadly obovate, 10-16 × (5-)6-9(-10) mm, claw 5-9 mm, apex rounded; filaments (5-)7-10 mm; anthers 1.5-2.5 mm.
spreading to ascending, smooth or slightly torulose, terete, (3.5-)5-10(-11) cm × (2.5-)3.5-5 mm; valvular segment with 12-20(-30) seeds per locule, (3-)4-8.5(-9.5) cm, terminal segment usually seedless, rarely 1 or 2-seeded (attenuate-conic, thin), (5-)9-16 mm.
dark brown to black, light brown, or reddish, 1.8-2.7(-3) mm diam.; seed coat finely reticulate-alveolate, not mucilaginous when wetted.
Flowering May-Sep. Roadsides, disturbed areas, waste places, cultivated and abandoned fields, escape from cultivation; 0-500 m; introduced; Alta., B.C., Man., N.B., Nfld. and Labr., N.W.T., N.S., Ont., P.E.I., Que., Sask.; Alaska, Ariz., Ark., Calif., Colo., Conn., Del., D.C., Fla., Ga., Idaho, Ill., Ind., Iowa, Ky., La., Maine, Md., Mass., Mich., Miss., Mo., N.H., N.J., N.Y., N.C., Ohio, Okla., Oreg., Pa., Tenn., Utah, Vt., Va., Wash., W.Va., Wis.; Europe; Asia; Africa; introduced also in Mexico, Central America, South America, Atlantic Islands, Australia.
is both a crop and a sporadically occurring naturalized weed in North America, grown in two forms recognized by some as subspecies. Subspecies
(rape, rapeseed, or canola) is an annual with slender roots widely cultivated as an oil crop and is the most commonly naturalized. Subspecies
Metzger [= subsp.
(Linnaeus) Hanelt] (rutabaga, swede, or Swedish turnip) is a biennial with fleshy roots that rarely escapes from cultivation.
has been reported as a weed from most southeastern states, it is very likely that most reports represent misidentifications of
(I. A. Al-Shehbaz 1985). It is difficult to distinguish between plants of
that lack flowers and proximal leaves.
is an allotetraploid derived from hybridization between the
= 9) and
= 10). Its center of origin is uncertain but likely Mediterranean Europe, with molecular data supporting evidence of multiple independent origins between the parental taxa
and its related
= 9 species (Song K. et al. 1993). Specimens from West Virginia have not been observed.