The Australian santalum species
The Santalum genus is part of the sandalwood family (Santalaceae). Members of the Santalum genus can be found in Southeast Asia, Australia and some Pacific islands. A number of these shrubs and trees are renowned for their aromatic wood and oils. Santalums are root hemi-parasites. These plants attach their roots to the roots of other plants. This connection (or haustoria) allows the parasitic tree to gain some of their nutrient and water requirements from the host species.
Australia has six species of Santalum. Some are being researched with a view to developing commercially viable food and/or timber crops.
Santalum acuminatum is also known as quandong, sweet quandong or native peach. It grows to 6 metres and is widespread in inland Australia. It is prized as a source of food (fruit) for aboriginal Australians and is being grown more and more as a food crop. It has a spindly, erect trunk and an open crown of pale olive-green, lanceolate leaves. The flowers are clusters of small, creamy white blossoms which areborne at the ends of stems. Flowers appear randomly throughout the year. The edible, fleshy fruits which follow are shiny and red.
Santalum lanceolatum (northern sandalwood) is native to northern and central Australia. It has weeping, spreading branches with lance shaped leaves. The flowers may be cream or a pale green and appear in the leaf axils or in clusters at the ends of branches. The flowering season is from spring to summer. The fruits are a dark, purplish blue.
Santalum murrayanum (bitter quandong) grows to 4.5 metres with a 3 metre spread. It is native to the semi-arid regions of southern Australia. The weeping branches have distinctive, narrow leaves which may be yellowish-green to grey-green. The short leaves have hooked tips. Yellowish flowers appear from late winter to mid-summer. The fruits vary from green to a brownish red.
Santalum obtusifolium is one of several species with the common name of sandalwood. It is an erect suckering shrub with dark green, narrow leaves. The margins of the leaves curl under. The globular fruits are blue-black in colour.
Santalum spicatum (Australian sandalwood) and Santalum album (Indian sandalwood) are both grown in Australia and are traded internationally. India supplies only enough sandalwood for its domestic needs. Western Australia now supplies about 60% of the world’s sandalwood.
The heartwood of the sandalwood produces an essential oil which is used in cosmetics, soaps, and medicines.
Although once widespread throughout the southern part of the state, natural stands of sandalwood are now rare. Indiscriminate harvesting of the trees, and clearing of vast areas for agriculture finally resulted in controls being introduced to prevent the total extinction of the tree.
Plantations of Australian sandalwood are found throughout the wheatbelt area of Western Australia with Indian sandalwood also being grown in the Ord River irrigation area in the far north of the state. The plantations have a particular benefit in areas where soil salinity precludes the growing of many other crops.
Sandalwood oil has many medicinal qualities including anti-inflammatory and antibacterial properties. It is also useful in the treatment of hypertension and blood pressure problems.
Santalums grow naturally in warm, low rainfall areas. They like light, well-drained soil although they will tolerate saline soils and periods of dryness. They do not like poor drainage or any disturbance of their roots. Plantation crops are often from grafted stock.
