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: Hickory Wattle

General Information

Acacia falciformis is an evergreen, large, spreading shrub growing 5 - 8 metres tall, or a tree that usually grows up to 12 metres tall, occasionally taller, exceptionally to 24 metres on very favoured sites. The bole of the largest trees can be up to 75cm in diameter, though in the far north of its range it can become a spindly shrub with a stem not exceeding 3cm in diameter[, ]. 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 tree is harvested from the wild as a source of wood and tannins. It has been harvested commercially for its tannins in the past. It is planted for use in shelterbelts and for soil stabilization.

Known Hazards

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 - Victoria, New South Wales, Queensland

Habitat

Found in clay loam in sclerophyll forest or woodland, mostly at elevations from 800 - 1,200 metres[].
Common on moderate to steep slopes in hilly and mountainous country and it extends to gentle slopes[].

Properties

Medicinal Rating
Other Uses Rating
Habit	Evergreen Tree
Height	8.00 m
Growth Rate	Fast
Pollinators	Insects
Cultivation Status	Cultivated, Wild

Cultivation Details

Acacia falciformis extends from the warm temperate to the moist tropical zones of eastern Australia, where it is found at elevations up to 1,500 metres. It grows best in areas where annual daytime temperatures are within the range 18 - 32°c, but can tolerate 7 - 40°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 600 - 800mm, but tolerates 500 - 900mm[].
Requires a sunny position[]. Succeeds in a wide range of well-drained soils of medium or low fertility[]. Prefers a pH in the range 5.5 - 7, tolerating 5 - 7.5[]. Established plants are very drought tolerant[].
A fast-growing tree[].
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[].
Acacia falciformis appears to hybridise with Acacia bancroftiorum where their ranges overlap[].

Edible Uses

None known

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:

A useful species for erosion control and shelterbelts on steep slopes and poor soils[, ].

Other Uses

The bark contains 25 - 30% tannins and has been harvested on a commercial basis in the past[]. Bark harvested for its tannins should only be taken from mature stems, and only when the sap is rising at the beginning of the growing season - which is when the tannin content is highest and the bark is most easily removed from the wood[].

The heartwood is pale-coloured and there is a narrow band of sapwood. The wood is heavy, tough and durable. It can be used for tool handles, posts, poles[]
The wood can be used for fuel and to make charcoal[].

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[].