Acacia citrinoviridis

Acacia citrinoviridis, commonly known as river jam, milhan or wantan, is a species of flowering plant in the family Fabaceae and is endemic to north-western Western Australia. It is a graceful tree with fissured grey bark, shiny reddish brown branchlets, narrowly elliptic, leathery phyllodes, spikes of bright yellow flowers, and narrowly oblong pods with citron green or silvery white hairs.

Description

A shrub or small tree. It grows 5 m tall. There are prickles along the stem. The leaves are twice divided and there are 8-18 pairs of pinnae. There are up to 50 pairs of pinnules on each pinnae. The flowers are yellow. They are in large clusters at the ends of branches. The pods are flattened.

Edible Uses

Seed - raw or cooked. It can be eaten in the same ways as other small legume seeds and is also ground into a powder then used as a flavouring in desserts or as a nutritious supplement to pastries and breads. Traditionally, the seed is coarsely ground then dried and eaten raw. The straight seedpods are 25 - 120mm long, 7 - 15mm wide, containing black or dark brown, almost globose seeds 5 - 6.5mm in diameter. Acacia seeds are highly nutritious and contain around 26% protein, 26% available carbohydrate, 32% fibre and 9% fat. The fat content is higher than most legumes with the aril providing the bulk of fatty acids present. These fatty acids are largely unsaturated. The energy content is high in all species tested, averaging 1480 ±270 kJ per 100g. The seeds are low glycaemic index foods - the starch is digested and absorbed very slowly, producing a small, but sustained rise in blood glucose and so delaying the onset of exhaustion in prolonged exercise. The ground seed can be used to produce a high quality, caffeine-free coffee-like beverage. An edible gum can be obtained from lesions on the trunk.

Traditional Uses

The seeds are coarsely ground then eaten uncooked.

This uses section is brief — help expand it

Medicinal Uses

The bark of all Acacia species contains greater or lesser quantities of tannins and are astringent. Astringents are often used medicinally - taken internally, for example. they are used in the treatment of diarrhoea and dysentery, and can also be helpful in cases of internal bleeding. Applied externally, often as a wash, they are used to treat wounds and other skin problems, haemorrhoids, perspiring feet, some eye problems, as a mouth wash etc. Many Acacia trees also yield greater or lesser quantities of a gum from the trunk and stems. This is sometimes taken internally in the treatment of diarrhoea and haemorrhoids.

Known Hazards

The seed of many Acacia species, including this one, is edible and highly nutritious, and can be eaten safely as a fairly major part of the diet. Not all species are edible, however, and some can contain moderate levels of toxins. Especially when harvesting from the wild, especial care should be taken to ensure correct identification of any plants harvested for food. Especially in times of drought, many Acacia species can concentrate high levels of the toxin Hydrogen cyanide in their foliage, making them dangerous for herbivores to eat.

Distribution

It grows in sandy rocky creek beds. It needs a well drained soil and sunny position.

Where It Grows

Australia*,

Cultivation

It is grown from seed.

Propagation

The seed of most, if not all, members of this genus has a hard seedcoat and may benefit from scarification before sowing to speed up germination. This can usually be done by pouring a small amount of nearly boiling water on the seeds (being careful not to cook them!) and then soaking them for 12 - 24 hours in warm water. By this time they should have imbibed moisture and swollen - if they have not, then carefully make a nick in the seedcoat (being careful not to damage the embryo) and soak for a further 12 hours before sowing. Acacia seeds that have matured fully on the bush and have been properly dried have a hard seed coat and can be stored in closed containers without deterioration for 5 - 10 years or more in dry conditions at ambient temperatures. It is best to remove the aril, which attracts weevils and can lead to moulds forming. The arils are easilyremoved by placing the seeds in water and rubbing them between the hands, then drying the seeds and winnowing them.

Other Uses

The heartwood is dark brown, hard, dense and moderately durable. It can be used for small posts and rough building timbers, and has potential for conversion into small decorative items. It was used traditionally to make items such as boomerangs, fighting sticks and spears. The dense wood makes an excellent fuel. Acacia citrinoviridis has a dense crown and is useful for providing shade, shelter and windbreaks. The plant's bushy, root-suckering habit makes it especially suitable for soil protection and plantings to reduce scouring of alluvial deposits during flash floods in arid and semi-arid regions.

Notes

There are about 1,350 Acacia species. Over 1,000 occur in Australia. Also as Mimosaceae.

Also Known As

Milhan, Wantan

References (5)

• Doran, J.C., & Turnbull, J.W. (Eds), 1997, Australian Trees and Shrubs: species for land rehabilitation and farm plantings in the tropics. ACIAR Monograph No 24. p 126
• Elliot, W.R., & Jones, D.L., 1982, Encyclopedia of Australian Plants suitable for cultivation. Vol 2. Lothian. p 31
• Nuytsia 2:86. 1976
• Scott, M.P., 1972, Some aboriginal plant foods from the Ashburton district, Western Australia. Western Australian Naturalist 12(4):94-96.
• Paczkowska, G . & Chapman, A.R., 2000, The Western Australian Flora. A Descriptive Catalogue. Western Australian Herbarium. p 302

More from Fabaceae

Vicia nipponica

Vicia noeana

Vicia palaestina

Vicia pannonica

Vicia paucifolia

Vicia peregrina

Broad-podded vetch