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PRICKLY LETTUCE Lactuca serriola (Asteraceae) Height to 1.75m. Upright and stiff biennial, the upper part of which is branched. Broken stems exude a milky sap. Grows on disturbed and waste ground, verges and railways. FLOWERS are borne in heads, 11-13mm across, with yellow florets; carried in open, branched inflorescences (Jul-Sep). FRUITS are brown with unbranched pappus hairs. LEAVES are grey-green and held stiffly erect with pointed clasping bases; margins and lower midrib have weak spine; lower leaves may have narrow lobes. STATUS-Common only in S.