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bird's rape, bird-rape, canola, common mustard, field-mustard, rape, rapeseed, turnip, turnip-rape, wild-rape, wild-turnip

Habit Annuals or biennials; (roots fleshy or slender); (green to slightly glaucous), glabrous or sparsely hairy. Annuals, biennials, or perennials [shrubs]; eglandular.
Stems

unbranched or branched distally, 3–10 dm.

Basal leaves

petiole (winged), (1–)2–10(–17) cm;

blade ± lyrate-pinnatifid to pinnate to pinnatisect, (5–)10–40(–60) cm × 30–100(–200) mm, (margins sinuate-dentate, sometimes ciliate), lobes 2–4(–6) each side, (terminal lobe oblong-obovate, obtuse, large, blade surfaces usually setose).

Cauline leaves

(middle and distal) sessile;

base auriculate to amplexicaul, (margins subentire).

petiolate or sessile;

blade base auriculate or not, margins entire, dentate, serrate, or pinnately lobed.

Racemes

not paniculately branched, (with open flowers overtopping or equal to buds).

usually ebracteate, often elongated in fruit.

Flowers

sepals (3–)4–6.5(–8) × 1.5–2 mm;

petals deep yellow to yellow, obovate, 6–11(–13) × (2.5–)3–6(–7) mm, claw 3–7 mm, apex rounded;

filaments 4–6(–7) mm;

anthers 1.5–2 mm.

actinomorphic;

sepals erect, ascending, or spreading, lateral pair saccate or not basally;

petals white, cream, yellow, pink, lilac, lavender, or purple, claw present, often distinct;

filaments unappendaged, not winged;

pollen 3-colpate.

Fruiting pedicels

ascending to spreading, (5–)10–25(–30) mm.

Fruits

ascending to somewhat spreading, torulose, terete, (2–)3–8(–11) cm × 2–4(–5) mm;

valvular segment with 8–15 seeds per locule, (1.3–)2–5(–7.5) cm, terminal segment seedless, 8–22 mm.

silicles or siliques, dehiscent or indehiscent, usually segmented, usually latiseptate or terete (subterete or 4-angled in Erucastrum) [angustiseptate];

ovules (1–)2–276[–numerous] per ovary;

style usually distinct (absent in Cakile, obscure in Carrichtera, obsolete in Eruca);

stigma entire or strongly 2-lobed (sometimes slightly 2-lobed in Cakile).

Seeds

black, brown, or reddish, 1.1–2 mm diam.;

seed coat very finely reticulate-lightly alveolate, not mucilaginous when wetted.

biseriate, uniseriate, or aseriate;

cotyledons usually conduplicate, rarely accumbent or incumbent (in Cakile).

Trichomes

absent or simple.

2n

= 20.

Brassica rapa

Brassicaceae tribe Brassiceae

Phenology Flowering Apr–Sep.
Habitat Roadsides, disturbed areas and waste places, cultivated fields, grain fields, orchards, gardens
Elevation 0-1500 m [0-4900 ft]
Distribution
from FNA
AK; AL; AR; AZ; CA; CO; CT; DC; DE; FL; GA; IA; ID; IL; IN; KS; KY; LA; MA; MD; ME; MI; MN; MO; MS; MT; NC; ND; NE; NH; NJ; NM; NV; NY; OH; OK; OR; PA; RI; SC; SD; TN; TX; UT; VA; VT; WA; WI; WV; WY; AB; BC; MB; NB; NL; NS; NT; ON; PE; QC; SK; YT; Europe; Asia; Africa [Introduced in North America; introduced also in Mexico, West Indies, Central America, South America, Atlantic Islands, Australia]
[WildflowerSearch map]
[BONAP county map]
North America; Eurasia; n Africa [Introduced widely]
Discussion

Brassica rapa is widely cultivated as an oil crop and vegetable, and cultivars, especially in Asia, have been recognized as species, subspecies, and varieties. The most important crops include: rapeseed or canola, turnip (subsp. rapa), Chinese mustard or pakchoi [subsp. chinensis (Linnaeus) Hanelt], and Chinese cabbage or petsai [subsp. pekinensis (Loureiro) Hanelt]. The species is also a widespread naturalized weed [subsp. sylvestris (Linnaeus) Janchen] throughout temperate North America and elsewhere. It is self-incompatible. Hybridization in the field in Europe has been described between B. napus and B. rapa (R. B. Jørgensen and B. Andersen 1994).

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Genera 46, species ca. 245 (13 genera, 28 species in the flora).

The generic boundaries in Brassiceae are largely artificial, and the number of genera may be substantially reduced.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Source FNA vol. 7, p. 423. FNA vol. 7, p. 419.
Parent taxa Brassicaceae > tribe Brassiceae > Brassica Brassicaceae
Sibling taxa
B. elongata, B. fruticulosa, B. juncea, B. napus, B. nigra, B. oleracea, B. tournefortii
Subordinate taxa
Synonyms B. campestris, B. campestris var. oleifera, B. chinensis, B. pekinensis, B. rapa subsp. chinensis, B. rapa subsp. pekinensis, Sinapis pekinensis
Name authority Linnaeus: Sp. Pl. 2: 666. (1753) de Candolle: Mém. Mus. Hist. Nat. 7: 242. (1821)
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