Sticky groundsel

Senecio viscosus (sticky groundsel, stinking groundsel) is an erect herbaceous annual of the daisy family (Asteraceae) growing up to about 70 cm tall, the entire plant densely covered with conspicuous sticky glandular hairs that give off an unpleasant resinous odour when bruised. The stout, branching stem bears alternate, sticky-glandular, deeply pinnately lobed leaves 3–8 cm long with toothed segments. From midsummer to autumn it produces loose corymbs of cylindrical-conical yellow flower heads each about 10 mm long; the small spreading ray florets soon roll back tightly under the head, and the outer involucral bracts characteristically have dark brown tips and project at the base of the head. The fruit is a hairy, ribbed achene topped with a fine white pappus that aids wind dispersal. Native to disturbed sandy or gravelly ground, railway ballast, dunes, and waste places across Europe, it is locally common in Britain and Ireland and has been introduced to many parts of North America from British Columbia and the northeastern United States to Newfoundland.