Teetulpa-weed

Diplotaxis muralis is an annual or short-lived perennial herb of the cabbage family growing 10-50 cm tall with leafy basal rosettes and erect to ascending, branched, often glaucous stems. Leaves are mainly basal, oblanceolate to pinnatifid, 4-15 cm long, with rounded, coarsely toothed or pinnately lobed margins; stem leaves are few and reduced. Inflorescences are loose, open terminal racemes of small four-petalled flowers 6-10 mm across; petals are bright yellow, often fading paler, with claws shorter than the limb. Fruits are erect to ascending, narrowly cylindrical siliques 15-30 mm long held on slender pedicels 8-15 mm, somewhat constricted between the seeds and tipped with a short conical beak. Seeds are arranged in two rows within each loculus, a distinctive feature of the genus. The species favours dry waste ground, walls, roadsides, and cultivated land throughout the Mediterranean basin and western Europe, flowering from late spring through autumn.