Plants of South Eastern New South Wales
Rapistrum rugosum
Common name
Turnip Weed, Giant Mustard
Family
Brassicaceae
Where found
Weed of urban bushland, pastures, disturbed sites, roadsides, crops, and waterways. Mainly Sydney area and along highways. Occasionally elsewhere. Doubtfully naturalised in the ACT.
Notes
Introduced annual or biennial herb to more than 1 m tall, somewhat glaucous, bristly, the coarse hairs scattered to frequent. Leaves basal and alternating up the stems, to 25 cm long, margins lobed to dissected, and toothed. Flowers with 4 yellow petals with darker veins, each 5–10 mm long. Flowers in clusters at the tops of the stems. Flowers mainly summer–autumn. Seed cases 5–10 mm long including the beak, breaking between the upper and lower segments, the lower segment 2.5–3.5 mm long, to 1.5 mm wide, upper segment 3–6 mm long, 3–4 mm wide, ribbed, sometimes wrinkled, sometimes bristly.
PlantNET description: http://plantnet.rbgsyd.nsw.gov.au/cgi-bin/NSWfl.pl?page=nswfl&lvl=sp&name=Rapistrum~rugosum (accessed 4 February, 2021)
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