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

broccoli, brussel sprouts, cabbage, cultivated cabbage, kale, wild cabbage

Habit Annuals or biennials; (roots fleshy or slender); (green to slightly glaucous), glabrous or sparsely hairy. Biennials or perennials; (with slender taproot or woody caudex, becoming suffrutescent and covered with conspicuous leaf scars); (glaucous), glabrous.
Stems

unbranched or branched distally, 3–10 dm.

branched distally, 5–10 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).

petiole to 30 cm;

blade oblong or obovate, to 45 cm × 150 mm, (fleshy), blades pinnatifid or margins dentate.

Cauline leaves

(middle and distal) sessile;

base auriculate to amplexicaul, (margins subentire).

(distal) sessile;

blade (oblong to lanceolate), base auriculate and amplexicaul, (margins entire).

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 8–15 × 1.5–2.7 mm;

petals yellow, white, or lemon yellow, ovate or elliptic, (15–)18–25(–30) × (6–)8–12 mm, claw 7–15 mm, apex rounded;

filaments 8–12 mm;

anthers 2.5–4 mm.

Fruiting pedicels

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

spreading to ascending, (8–)14–25(–40) 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.

spreading to ascending, smooth, ± 4-angled or subterete, (2.5–)5–8(–10) cm × (2.5–)3–4(–5) mm;

valvular segment with 10–20 seeds per locule, (2–)3–7.5(–9) cm, terminal segment usually seedless, rarely 1 or 2-seeded, (conic), (3–)4–10 mm.

Seeds

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

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

brown, 1.7–2.5 mm diam.;

seed coat reticulate, not mucilaginous when wetted.

2n

= 20.

= 18.

Brassica rapa

Brassica oleracea

Phenology Flowering Apr–Sep. Flowering May–Aug.
Habitat Roadsides, disturbed areas and waste places, cultivated fields, grain fields, orchards, gardens Maritime slopes or sea-facing cliffs, weedy escape, gardens, abandoned fields, waste places
Elevation 0-1500 m [0-4900 ft] 0-100 m [0-300 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
CA; CT; IA; IL; KY; MA; NY; OH; PA; RI; TX; VT; NL; ON; PE; QC; Europe; Asia; Africa [Introduced in North America; introduced also in 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 oleracea is widely cultivated worldwide as a vegetable crop, and its various forms are generally recognized as varieties instead of subspecies; these include var. acephala de Candolle (kale and collards), var. botrytis Linnaeus (cauliflower), var. capitata Linnaeus (cabbage), var. gemmifera Zenk (Brussels sprouts), var. gongylodes Linnaeus (kohlrabi), and var. italica Plenk (broccoli). It also occurs sporadically as a weedy escape from cultivation and seems unlikely to persist for long periods of time. It is reported to be naturalized on coastal cliffs (maritime slopes) in the northern Central Coastal Region and the central and southern North Coastal Region in California (Marin, San Francisco, San Mateo, Santa Barbara, and Ventura counties) (J. T. Howell et al. 1958; Howell 1970; H. G. Baker 1972; R. C. Rollins 1993b).

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

Source FNA vol. 7, p. 423. FNA vol. 7, p. 423.
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. juncea, B. napus, B. nigra, 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 B. alboglabra
Name authority Linnaeus: Sp. Pl. 2: 666. (1753) Linnaeus: Sp. Pl. 2: 667. (1753)
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