Acacia oraria
Acacia oraria
Safety & 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.
Cultivation Details
Acacia oraria is a plant of the warm to hot, humid tropics, where it can be found at elevations up to 700 metres. The mean maximum temperature of the hottest month is 32 - 34°c, dropping to around 14 - 17°c in the coolest month. Frosts are absent, The mean annual rainfall can range from 900 - 2,150mm[1]. Requires a sunny position. Found in the wild in deep, calcareous beach sands with shell grit or yellow earths - the soils are usually infertile, ranging from acidic to alkaline, and may be saline or subsaline. In Indonesia it is common on shallow soils over limestone[1]. The plant is highly tolerant of saline soils[1]. Plants are tolerant of seasonal inundation of the soil[1]. The plant is grown as an ornamental in Indonesia, where it is often used for street planting[1]. The plant coppices fairly well[1]. 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[1].
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[2]. Cite as: Tropical Plants Database, Ken Fern. tropical.theferns.info. 2026-02-19. <tropical.theferns.info/viewtropical.php?id=Acacia+oraria>
Pollinators
Insects
References
- [1]Australian Trees and Shrubs: Species for Land Rehabilitation and Farm Planting in the Tropics — Doran J.C.; Turnbull J.W. (Editors) · Australian Centre for International Agricultural Research; Canbe · 1997 · ISBN 1-86320-127-0 ↩︎A very informative book, rich in information about the uses, cultivation needs and very much more for over 160 species of Australian trees and shrubs.
- [2]Potential of Australian Acacias in combating hunger in semi-arid lands — Rinaudo A.; Patel P.; Thomson L.A.J. · 2002 ↩︎
- [3]Flora of Australia — http://www.anbg.gov.au/abrs/abif/flora/ ↩︎The full information from the Flora of Australia - on-line. An excellent resource.
- [4]Australian Tropical Rainforest Plants — http://www.anbg.gov.au/cpbr/cd-keys/rfk/index.html ↩︎An online resource giving botanical information, and a little bit about plant usage, for over 2,700 species of plants found in the Australian rainforest.
- [5]The Useful Native Plants of Australia. — Maiden J.H. · Turner & Co.; London. · 1889 · http://www.biodiversitylibrary.org ↩︎Terse details of the uses of many Australian plants and other species naturalised, or at least growing, in Australia. It can be downloaded from the Internet.
- [6]Plant Resources of Southeast Asia — http://proseanet.org/ ↩︎Lots of information on the uses of the plants of SE Asia.
- [PFAF]Plants for a Future — pfaf.org ↩︎