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:

General Information

Acacia jennerae is a shrub or a tree that can grow 2 - 6 metres tall[]. It is sometimes single-stemmed but more commonly divides at ground level into 2 or more, straight, rather slender stems[]. The plant often suckers and can form dense thickets[, ]. Although it produces true leaves as a seedling, llike most members of this section of the genus, the mature plant does not have true leaves but has leaf-like flattened stems called phyllodes[].
The plant is harvested from the wild for local use as a food. It has been suggested as a potential commercial seed crop for areas such as Western Australia and other hot, dry regions of the world[]. The plant can be used as a soil stabilizer and wind shelter and also has potential as an ornamental[].

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 - New South Wales, South Australia, Western Australia, Northern Territory

Habitat

Arid and semi-arid areas[]. Eucalyptus woodland, growing on acid to neutral sands and loams, commonly in dune swales or along drainage lines, including the margins of salt lakes[].

Properties

Edibility Rating
Medicinal Rating
Other Uses Rating
Habit	Tree
Height	4.00 m
Growth Rate	Medium
Pollinators	Insects
Cultivation Status	Wild

Cultivation Details

Acacia jennerae is a plant of the arid to semi-arid temperate and subtropical zones of Australia, where it is found at elevations up to 1,000 metres. It grows best in areas where annual daytime temperatures are within the range 12 - 30°c, but can tolerate 5 - 36°c[]. When dormant, the plant can survive temperatures down to about -10°c, but young growth is more tender can be severely damaged at -1°c[, ]. It prefers a mean annual rainfall in the range 250 - 300mm, but tolerates 200 - 350mm[].
Requires a sunny position[]. Grows best in a well-drained, sandy soil of moderate to low fertility[]. Tolerant of somewhat saline soils[]. Prefers a pH in the range 5.5 - 7, tolerating 5 - 7.5[]. Established plants are drought tolerant[].
Plants sucker freely and also coppice well. Although top growth is usually killed, the plants usually survive fires by resprouting at the base[, ].
Plants have a moderate rate of growth[].
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[].
In the past the species has commonly been confused with Acacia microbotrya, especially where their ranges overlap in Western Australia[].
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[, , ]. Highly regarded as a food by the native Aboriginal people of Australia, where the seed may be consumed either green or, if mature, can be roasted and ground into flour[]. 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[].
The seedpods are up to 15cm long and 6 - 8mm wide, with dull black, oblong seeds 6 - 8mm long[].
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 exudes from the trunk and branches[].

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 plant's suckering habit and salt tolerance suggest it would be useful for soil stabilisation in some saline areas. With age the plants attain a height and form suitable for use as a visual screen and in shelterbelt plantings as a low windbreak and for providing shade for stock and wildlife[].

Other Uses

The tree is a potential source of firewood in hot, dry areas[].

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[].