Olearia ballii, commonly known as mountain daisy, is a species of flowering plant in the family Asteraceae and is endemic to Lord Howe Island. It is a dense shrub with crowded linear leaves and small, purplish and white, daisy-like inflorescences. Description Olearia ballii is a dense shrub that typically grows to a height of up to . It has crowded, more or less sessile, linear leaves long and wide with the edges rolled under and white, woolly hairs on the lower surface. The heads or daisy-like "flowers" are arranged singly in on the ends of the branchlets and are in diameter and sessile, with softly-hairy bracts forming an involucre at the base. Each head has twenty to thirty ray florets, the white petal-like ligules up to long with purple tips, surrounding about forty purplish disc florets. Flowering mostly occurs between October and March and the fruit is an achene about long, the pappus bristles about long. Taxonomy Mountain daisy was first formally described in 1874 by Ferdinand von Mueller who gave it the name Aster ballii in Fragmenta Phytographiae Australiae. In 1896, William Hemsley changed the name to Olearia ballii in the Annals of Botany. The specific epithet (ballii) honours Lieutenant Henry Lidgbird Ball who, while commanding HMS Supply in 1788, discovered and named Lord Howe Island, where the plant was subsequently collected. Distribution and habitat Olearia ballii is endemic to Australia’s Lord Howe Island where it grows on the southern mountains and is common at altitudes above . References Asterales of Australia ballii Endemic flora of Lord Howe Island Plants described in 1896 Taxa named by Ferdinand von Mueller