Oldman Saltbush

Description

Atriplex nummularia is a species of saltbush from the family Amaranthaceae and is a large woody shrub known commonly as oldman saltbush. A. nummularia is native to Australia and occurs in each of the mainland states, thriving in arid and semi-arid inland regions. Atriplex nummularia is a perennial halophyte species that is extremely hardy, thriving in particularly harsh environments such as saline and alkaline lowlands. A. nummularia is the largest species of Australian saltbush, typically growing 2–4m wide and up to 3m tall in either a sprawling or erect arrangement. It develops a lattice of woody stems which branch from or close to ground level and utilises a taproot with a subsequent root system that is moderate to deep. It is a deciduous plant, with simple alternate leaves that often have dull teeth and are irregular in shape, varying between circular and triangular. The leaves range between 1–5 cm long and have a silvery-grey coating on both sides with a scaly texture. Although hermaphroditic variations with bisexual flowers have been reported this species is generally regarded as dioecious, with male and female flowers occurring on separate plants. The male flowers are at the ends of branches in disjunct beads, whereas the female flowers grow along panicles in dense clusters typically around 20 cm in length. After the female flower has been fertilised, leafy bracts become enlarged and surround the developing seed. The seeds themselves are typically round with a thick, woody seed coat and an overall reddish-brown appearance. Attached only at the base, the fruiting bracteoles are fan shaped and generally grow between 0.5–1 cm wide. Originally a native Australian plant, Atriplex nummularia naturally occurs New South Wales, the Northern Territory, Queensland, South Australia, Victoria and Western Australia. It usually occurs on saline, low-lying clay soils such as floodplains, but is highly adaptable and can occur in most soils. Atriplex nummularia also thrives in temperate and sub-tropical regions of the world,occurring throughout Taiwan and many parts of Oceania. It has also been introduced to most Middle-Eastern and North African countries, as well as South Africa, Mexico, Chile, Spain and the USA. A. nummularia is typically found in lowland areas such as floodplains in both the Northern and Southern hemispheres, flavouring saline clay soils.