Centipeda minima

Centipeda minima, commonly called spreading sneezeweed or gukwonderuk, is a small prostrate annual herb of the family Asteraceae, widely distributed across temperate and subtropical Asia, Australia and the Pacific. Plants typically reach only 5 to 20 centimetres in spread, with slender, much-branched stems lying flat on the ground or weakly ascending. The leaves are alternate, small, obovate to spatulate, 5 to 15 millimetres long, with a few coarse teeth toward the apex. Flower heads are inconspicuous, sessile or nearly so in the leaf axils, hemispherical to subglobose, only 2 to 4 millimetres across, lacking ray florets — composed of numerous tiny greenish to yellowish female florets around the margin and a few perfect disc florets in the centre. Fruits are small four-angled cypselae. Crushing the plant releases a strong pungent aroma that can induce sneezing, accounting for its English common name.