Acacia cultriformis (Knife-leaf Wattle)

Native to southeastern Queensland and New South Wales, Australia, this evergreen shrub or small tree usually reaches about 8 feet tall. Its distinctive triangular, knife-shaped foliage consists of flattened leaf stalks called phyllodes rather than ordinary leaf blades. Golden, ball-shaped flowerheads appear in spring. It is grown as an ornamental foliage shrub and has been introduced to California and southern Africa. Outside its native range, it has become an environmental weed in the Australian Capital Territory and parts of New South Wales. Photographed in Colombia.