Biddy-biddy (Acaena novae-zelandiae)
Other common names
Bidibid, Bidgee-widgee, Piri-piri-bur
Perennial that grows four to eight inches tall. Biddy-biddy spreads by stolons that root at the nodes, and plants form large mats where individual plants are indistinguishable. The plant stems are prostrate to erect depending on conditions. Leaves alternate and are compound, with mature plants having 5 to 11 leaflets, 1/4 to 2/3 inches long. Flower heads are spherical, and turn into a round bur that disperses as a unit when mature.
This plant prefers open, disturbed, well-drained sites, including stable dunes, open scrub, grassy areas, and trampled sites in coastal habitats where some summer moisture is available and frosts are infrequent. Plants thrive on poor soils and compete poorly with established vegetation.