Tithonia diversifolia (Mexican Sunflower)

Native to Mexico and Central America, this fast-growing shrub in the daisy family reaches about 10 feet tall. Its broad, hairy leaves usually have three to five pointed lobes. Yellow flower heads about 4 inches across contain outer ray florets surrounding a dense center of tiny disc florets. It grows along roadsides and in disturbed ground and is used as a hedge, livestock fodder, and green manure. It has naturalized in Colombia, where it grows between about 330 and 6,600 feet. It is invasive in Queensland, Australia, forming dense thickets that displace native vegetation. Photographed in the central Andes mountain range of Colombia.