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

brown mustard, Chinese, Chinese mustard, Chinese or brown or Indian or leaf mustard, India mustard, Indian, Indian mustard, leaf mustard, mustard-greens

Habit Annuals or biennials; (roots fleshy or slender); (green to slightly glaucous), glabrous or sparsely hairy. Annuals; (± glaucous), ± glabrous.
Stems

unbranched or branched distally, 3–10 dm.

branched distally, 2–10 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).

(early deciduous);

petiole (1–)2–8(–15) cm;

blade pinnatifid to pinnately lobed, (4–)6–30(–80) cm × 15–150(–280) mm, lobes 1–3 each side.

Cauline leaves

(middle and distal) sessile;

base auriculate to amplexicaul, (margins subentire).

usually shortly petiolate, rarely sessile;

blade (oblong or lanceolate, reduced in size distally), base tapered or cuneate, not auriculate or amplexicaul, (margins dentate to lobed).

Racemes

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

not paniculately branched.

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.

sepals (3.5–)4–6(–7) × 1–1.7 mm;

petals pale yellow, ovate to obovate, (7–)9–13 × 5–7.5 mm, claw 3–6 mm, apex rounded or emarginate;

filaments 4–7 mm;

anthers 1.5–2 mm.

Fruiting pedicels

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

spreading to divaricately ascending, (slender), (5–)10–15(–20) 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.

(sessile); spreading to divaricately ascending to nearly erect (not appressed to rachis), torulose, subcylindrical or somewhat flattened, (2–)3–5(–6) cm × 2–5 mm;

valvular segment with 6–15(–20) seeds per locule, (1.5–)2–4.5 cm, terminal segment seedless (conic), (4–)5–10(–15) mm, (tapering to slender style).

Seeds

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

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

brown or yellow, 1.2–2 mm diam.;

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

2n

= 20.

= 36.

Brassica rapa

Brassica juncea

Phenology Flowering Apr–Sep. Flowering May–Sep.
Habitat Roadsides, disturbed areas and waste places, cultivated fields, grain fields, orchards, gardens Roadsides, disturbed areas, waste places, cultivated and abandoned fields, garden escape from cultivation
Elevation 0-1500 m [0-4900 ft] 0-3000 m [0-9800 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]
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; Europe; Asia; Africa [Introduced in North America; introduced also in Mexico, West Indies, Central America, South America, Australia]
[WildflowerSearch map]
[BONAP county map]
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.)

Brassica juncea is cultivated in North America primarily as a vegetable and condiment, and is currently being developed as an oilseed crop in western Canada. Its greatest diversity of forms occurs in Asia, where the species is widely cultivated as a vegetable and as an oilseed crop (I. A. Al-Shehbaz 1985). Two main variants are distinguished on the basis of seed color: oriental mustard is yellow-seeded, and brown or Indian mustard is brown-seeded. The species is an allotetraploid derived from hybridization between B. nigra (n = 8) and B. rapa (n = 10). Its center of origin is uncertain but is most likely the Middle East, with possibly independent multiple origins within overlapping ranges of the putative parental taxa (S. I. Warwick and A. Francis 1994). Specimens from Delaware, District of Columbia, and Mississippi have not been observed, but are still listed here.

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

Source FNA vol. 7, p. 423. FNA vol. 7, p. 421.
Parent taxa Brassicaceae > tribe Brassiceae > Brassica Brassicaceae > tribe Brassiceae > Brassica
Sibling taxa
B. elongata, B. fruticulosa, B. juncea, B. napus, B. nigra, B. oleracea, B. tournefortii
B. elongata, B. fruticulosa, B. napus, B. nigra, B. oleracea, B. rapa, B. tournefortii
Synonyms B. campestris, B. campestris var. oleifera, B. chinensis, B. pekinensis, B. rapa subsp. chinensis, B. rapa subsp. pekinensis, Sinapis pekinensis Sinapis juncea, B. japonica, B. juncea var. crispifolia, B. juncea var. japonica
Name authority Linnaeus: Sp. Pl. 2: 666. (1753) (Linnaeus) Czernajew: Consp. Pl. Charcov., 8. (1859)
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