Acacia crassicarpa
Acacia crassicarpa
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
Occurs mainly at low elevations in the humid and sub-humid tropics[1]. It is found in areas where the mean annual rainfall can range from as low as 500 mm to as high as 3,500 mm, with a dry season of 3 - 6 months[1]. The mean minimum temperature of the coolest month is 15 - 22°c, and the mean maximum temperature of the hottest month is 31 - 34°c[310. It does not experience frost in its natural range[1]. Found in the wild on a variety of soil types, from calcareous beach sands, yellow earths derived from granite, red earths on basic volcanic rock to alluvial and colluvial soils derived from a variety of parent material[1]. Plants appear to be tolerant of salt spray and soil salinity[1]. Established plants are drought tolerant[2]. The tree has been widely planted in the tropics, often to provide shade on beaches[3], and has often escaped and become naturalised[4]. This is one of the fastest growing tropical Acacia spp. It appears to maintain active shoot growth almost the year round, although a few months of stagnation may occur in the dry season[1]. Under favourable conditions, seedlings grow rapidly reaching 25 - 30 cm tall in 3 - 4 months[1]. Flowering starts as early as 18 months after planting, while seed is produced in abundance after 4 years. Seeds mature 5 - 6 months after flowering[1]. Plants have attained a mean height of 15 - 23 metres and a mean diameter of 10 - 16 cm in 4 years, outperforming other fast-growing Acacia species including Acacia auriculiformis and Acacia mangium[1]. Trees do not coppice well[1]. In open situations, the crown is strongly branched and casts a moderate shade[1]. Preliminary observations indicate that Acacia crassicarpa is resistant to low-intensity fires[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[2].
Propagation
Seed - requires pre-treatment to break down the hard coat[5]. Pouring a small amount of boiling water over the seeds (which cools down quickly and so does not cook the seed), and then leaving to soak for 12 hours is usually effective, as is making a small incision in the coat to allow water to penetrate. Germination levels of 40 - 80% take place in 6 - 15 days[5]. Treated seeds are sown in germination beds, and seedlings are transplanted into polythene bags when they reach the 2-leaf-pair stage. Seeds can also be sown straight into polythene bags. Young seedlings should initially be kept at 50% sunlight, but this can be increased to 70% once they have been established. In general, 3 - 4 months are needed to raise seedlings to a plantable size, 25 cm in height[5]. Seeds stored in airtight containers at room temperature retain their viability for several years[5]. Cuttings. Air layering. Cite as: Tropical Plants Database, Ken Fern. tropical.theferns.info. 2026-02-19. <tropical.theferns.info/viewtropical.php?id=Acacia+crassicarpa>
Pollinators
Insects
References
- [1]Plant Resources of Southeast Asia — http://proseanet.org/ ↩︎Lots of information on the uses of the plants of SE Asia.
- [2]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.
- [3]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.
- [4]Pacific Island Ecosystems at Risk — http://www.hear.org/pier/scientificnames/index.html ↩︎A very good website detailing weed species that have been introduced into the Pacific Islands.
- [5]World Agroforesty Centre — http://www.worldagroforestry.org/ ↩︎An excellent online database of a huge range of trees giving very good information on each plant - its uses, ecology, identity, propagation, pests etc.
- [6]Flora Malesiana Series 1 — Various · Nationaal Herbarium Nederiand, Universiteit Leiden branch · http://www.archive.org ↩︎A massive treatment of the plants of the Malaysian Archipelago. Much of it has been made available to download from the Internet
- [7]Australian Native Plants Society — http://anpsa.org.au/index.html ↩︎A series of fact sheets on Australian plants. Good photographs, brief description and information on uses, habitat, range, cultivation etc.
- [8]Mansfeld's Database of Agricultural and Horticultural Plants — http://mansfeld.ipk-gatersleben.de/pls/htmldb_pgrc/f?p=185:3:4292127278597336 ↩︎Terse details of a huge range of useful plants.
- [9]IUCN Red List of Threatened Species — http://www.iucnredlist.org/ ↩︎A list of plants under threat and facing possible extinction, usually with brief details of the threats and information on habitat.
- [10]Philippine Medicinal Plants — http://www.stuartxchange.org/CompleteList.html ↩︎A lovely site, giving brief details on the medicinal uses of several hundred (over 400 at the last count) plants in the Philippines, plus a picture of each plant.
- [11]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.
- [PFAF]Plants for a Future — pfaf.org ↩︎