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: Longleaf Wattle

General Information

Acacia longissima is a slender shrub or a small spreading tree; it can grow up to 5 metres tall[]. 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 of its wood.

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

Mainly found in coastal areas, where it usually inhabits the borders of rainforests and it is sometimes locally common[]. Gullies in wet and dry sclerophyll forest, where it can grow in sandy to clay soils[].

Properties

Medicinal Rating
Other Uses Rating
Habit	Tree
Height	4.00 m
Pollinators	Insects
Cultivation Status	Wild

Cultivation Details

Acacia longissima is native to the temperate and subtropical zones of eastern Australia, where it just enters into the Tropics. It experiences occasional fosts, at least in the south of its range.
Requires a sunny position in a well-drained soil.
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[].
Closely related to Acacia longifolia, differing from it in its longer and narrower phyllodes and its much paler flowers. It differs from both Acacia courtii and Acacia orites in its shrub-like habit (unlike the latter two species, it is rarely a small tree)[].

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[].

Other Uses

This small tree yields wood available for minor articles of furniture, implements[].

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[].