Common names: Screw-pod wattle, Lightwood, Hickory wattle
Family name: Fabaceae
Category: 1a NEMBA
Description
Acacia implexa Benth. is an erect tree up to 15m tall, single-stemmed or divided near ground level into 2 or 3 main stems. Leaves dark green, narrowly-elliptic and sickle shaped, 7-20 cm long and 6-25 mm wide, much narrowed at the base. Bi-pinnate leaves may persist on young plants. Bark rough and greyish. Flowers arranged in globular heads, creamy to pale yellow, flowering from December to March. Pods narrow, coiled and twisted to 25 cm long, 4-7 mm wide. Seeds dark brown, longitudinal, fleshy tissue growing from the point of attachment of a seed.
Distribution
Screw-pod wattle is native in Australia.
History in South Africa
Acacia implexa has been recorded in the Western Cape at Tokai forest, Stellenbosch and Wolseley.
Environmental and economic impact
Screw-pod wattle is a fast growing tree and invades agricultural lands, planted forest and disturbed areas. It can become highly invasive if not controlled.
How it spreads
Screw-pod wattle spreads through suckers (side shoots or underground runners generate at the base of the tree).
How to eradicate
Currently control is by uprooting the plant. There are no herbicides registered for this species in South Africa.
Contact details
Alex Marsh
Email address: invasivespecies@sanbi.org.za
Tel: 021 799 8404
Photos:
Ernita van Wyk
References
- Australia National Heritage Trust. Acacia implexa. Available on http://thebegavalley.org.au/uploads/media/Lightwood_or_Hickory.pdf
- Eradication and monitoring of Australian acacias in South Africa s part of Early Detection and Rapid Response Program. Available on: http://archives.eppo.org/MEETINGS/2010_conferences/ias_trabzon/22_Wilson.pdf
- South African Plant Atlas. ARC-Plant Protection Research Institute. available on line http://www.dargleconservancy.org.za/documents/sapia08.pdf
- South African plants invaders atlas database. ARC- Plant protection research institute, Pretoria, South Africa. Available on: www.agis.agric.za