Classification of the genus Acacia (in the wider sense) has been subject to considerable debate. It is generally agreed that there are valid reasons for breaking it up into several distinct genera, but there has been disagreement over the way this should be done. As of 2017, it is widely (but not completely) accepted that the section that includes the majority of the Australian species (including this one) should retain the name Acacia, whilst other sections of the genus should be transferred to the genera Acaciella, Mariosousa, Senegalia and Vachellia[].

Common Name: Swamp Wattle

General Information

Acacia provincialis is a tree usually growing 5 - 6 metres tall with a spreading, openly-branched to dense crown. It sometimes reaches 8 - 10 metres on the wetter sites. A single-stemmed plant, though it sometimes divides into 2 - 4 main stems from low down, the trunk can be 10 - 30cm in diameter[].
The tree is harvested from the wild for local use as a food, medicine and source of materials. It is regarded as having reasonably good prospects as a crop plant for high volume wood production[]. The plant is cultivated as an ornamental in many warm temperate regions of the world, and is also grown at higher elevations in the tropics.

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.

Botanical References

Range

Australia - South Australia, Victoria

Habitat

Seasonally waterlogged or perpetually wet soils (acidic sand to clay) in swamps and along watercourses[]

Properties

Edibility Rating
Medicinal Rating
Other Uses Rating
Habit	Tree
Height	6.00 m
Growth Rate	Fast
Pollinators	Insects
Cultivation Status	Cultivated, Ornamental, Wild

Cultivation Details

Acacia provincialis is a plant of the temperate zone of southern Australia. In some parts of their range the plants are fairly frost-hardy, though in others they can be damaged by frosts[].
Requires a sunny position. Plants can tolerant low levels of salt in the soil[].
Plants can grow quickly when young, though that are usually rather short-lived and die when around 10 - 20 years old[].
Plants have been recorded as reaching a height of 3 metres within 2 years from seed, with trunks 10 - 15cm in diameter[].
Widely cultivated for horticultural purposes; although the flowers are unobtrusive they occur sporadically throughout much of the year, with the main flush in spring[].
Plants do not produce suckers, nor do they respond well to coppicing[].
Plants can be killed by fire, but they usually regenerate well though seeds in the soil that are stimulated to germinate by the heat of the fire[].
The seeds of most acacia species can be quickly and efficiently harvested at full maturity without the need for any specialised equipment. Small seed-bearing branches can be cut and beaten on sheets, or bushes can be beaten or shaken directly onto large sheets[].
This species has a symbiotic relationship with certain soil bacteria; these bacteria form nodules on the roots and fix atmospheric nitrogen. Some of this nitrogen is utilized by the growing plant but some can also be used by other plants growing nearby[].

Edible Uses

Seed - cooked. The seed are considered to have potential as a source of human food[]. 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[].
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[].

Medicinal

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[].

Agroforestry Uses:

The species is sometimes used for revegetation purposes in southern Australia, especially along roadverges[].
The plant is a useful species for a windbreak[].

Other Uses

The bark is a good source of tannins[].

Good quantities of gum are obtained from the plant, thoug not as much as is found on the closely related Acacia retinodes. The gum has good, solubility but the resulting solution is of low viscosity and this property, together with its dark colour, makes it unlikely to be of any commercial importance[].

The phyllodes can be used to dye wool a yellow to fawn colour with an alum mordant[].

The wood is exceptionally lightweight in relation to its volume[].

Propagation

Seed - best sown as soon as it is ripe in a sunny position in a warm greenhouse[].The dried 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. Sow the seed in Spring in a greenhouse. As soon as the seedlings are large enough to handle, prick them out into individual pots and grow them on in a sunny position in the greenhouse for their first winter. Plant them out in late spring or early summer, after the last expected frosts, and consider giving them some protection from the cold for their first winter outdoors.
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[].