Senecio vulgaris L.
groundsel
Erect, annual herb, 10-50 cm tall. Stems moderate to densely hairy when young, becoming glabrous or sparsely hairy, branched or not from base. Basal and lower cauline lvs sparsely to moderately hairy when young, becoming almost glabrous, petiolate or cuneately narrowed to stem; petiole < lamina, somewhat amplexicaul; lamina irregularly toothed to 1-pinnatifid, elliptic, narrow-obovate to oblong, acute, (1)-2-10 × (0.5)-1-3 cm; venation pinnate; segments ovate or oblong, irregularly dentate. Upper cauline lvs becoming smaller, narrower, apetiolate, and usually amplexicaul and toothed at base. Capitula in small panicles, dense at flowering, loose at fruiting. Supplementary bracts 8-21, lanceolate to triangular, 1-2.5 mm long. Involucral bracts (13)-18-21, linear, glabrous, 5.5-8 mm long. Ray florets 0. Disc dull yellow, 2-3-(4) mm diam. Achenes terete or slightly flattened, densely hairy between ribs, 1.8-2.8 mm long; pappus 4-7 mm long.
N.: throughout; S.: throughout except Westland, common in Canterbury; St.: Halfmoon Bay; Ch., C.
Europe, N. Africa, Asia 1867
Waste places, cultivated land, gardens, riverbeds and stony sites, from coastal areas to 700 m.
FL Jan-Dec.
Poisonous (Connor 1977).
Most N.Z. material is uniform in having rayless capitula, c. 20 involucral bracts, and numerous black-tipped, glabrous or sparsely hairy supplementary bracts, and so can be distinguished easily from S. sylvaticus and all erechtitoid senecios. In Europe, rayed forms sometimes occur but these have not as yet been collected in N.Z. In occasional plants there may be as few as 13 involucral bracts, as in S. sylvaticus.
