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

African mustard, Asian mustard, mustard, sahara mustard

Habit Annuals or biennials; (roots fleshy or slender); (green to slightly glaucous), glabrous or sparsely hairy. Annuals; densely hirsute proximally, glabrescent distally.
Stems

unbranched or branched distally, 3–10 dm.

usually branched basally, (widely) branched distally, (1–)3–7(–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).

(rosettes persistent);

petiole (broad) 2–10 cm;

blade lyrate to pinnatisect, 2–30 cm × 10–50(–100) mm, (margins serrate-dentate), 4–10 lobes each side.

Cauline leaves

(middle and distal) sessile;

base auriculate to amplexicaul, (margins subentire).

sessile;

blade (reduced in size distally, distalmost bractlike), base tapered, not auriculate or amplexicaul.

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 5–4.5 × 1–1.5 mm;

petals pale yellow, fading or, sometimes, white, oblanceolate, 4–7 × 1.5–2(–2.5) mm, claw 1–3 mm, apex rounded;

filaments 2.5–4 mm;

anthers 1–1.3 mm;

gynophore to 1 mm.

Fruiting pedicels

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

widely spreading, 8–15 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.

(shortly stipitate); widely spreading to ascending (not appressed to rachis), torulose, cylindric, 3–7 cm × 2–4(–5) mm;

valvular segment with 6–12(–15) seeds per locule, 2.2–5 cm, terminal segment 1(–3)-seeded, (cylindric, stout), 10–20 mm.

Seeds

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

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

light reddish brown or black, 1–1.2 mm diam.;

seed coat prominently reticulate, mucilaginous when wetted.

2n

= 20.

= 20.

Brassica rapa

Brassica tournefortii

Phenology Flowering Apr–Sep. Flowering Feb–Apr.
Habitat Roadsides, disturbed areas and waste places, cultivated fields, grain fields, orchards, gardens Roadsides, waste places, old fields, washes, open desert areas intermixed with desert shrubs
Elevation 0-1500 m [0-4900 ft] 0-800 m [0-2600 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
AZ; CA; NV; TX; UT; Europe; Asia; Africa [Introduced in North America; introduced also in nw Mexico, 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 tournefortii was first reported from California (Imperial, Riverside, and western San Bernardino counties) by W. L. Jepson ([1923–1925]), with the first collections appearing from southern California in 1941 (R. C. Rollins and I. A. Al-Shehbaz 1986), Arizona in 1959 (T. H. Kearney and R. H. Peebles 1960), Nevada in 1977, and Texas in 1978 (D. E. Lemke and R. D. Worthington 1991).

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

Source FNA vol. 7, p. 423. FNA vol. 7, p. 424.
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. oleracea, B. rapa
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) Gouan: Ill. Observ. Bot., 44, plate 20A. (1773)
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