Click on images to enlarge
infestation smothering a tree (Photo: Sheldon Navie)
old flowers (Photo: Sheldon Navie)
flower clusters (Photo: Sheldon Navie)
habit climbing a tree (Photo: Sheldon Navie)
habit growing on a fence (Photo: Sheldon Navie)
older stems with very large clusters of aerial tubers (Photo: Sheldon Navie)
close-up of an aerial tuber and reddish younger stems (Photo: Sheldon Navie)
habit (Photo: Sheldon Navie)
a "tuberling" removed from the ground (Photo: Sheldon Navie)
close-up of flowers (Photo: Sheldon Navie)
a seedling, or more accurately a "tuberling" (Photo: Sheldon Navie)
young drooping flower clusters (Photo: Sheldon Navie)
close-up of the heart-shaped leaves (Photo: Trevor James)
Anredera cordifolia (Tenore) Steenis
Anredera cordifolia subsp. gracilis (Miers) Xifreda & Argimón; Boussingaultia cordifolia Ten.; Boussingaultia gracilis Miers; Boussingaultia gracilis Miers forma gracilis; Boussingaultia gracilis Miers forma pseudobaselloides Hauman; Boussingaultia baselloides Kunth (misapplied)
Native to South America (Brazil, Bolivia, Colombia, Ecuador, Peru, Argentina, Paraguay and Uruguay).
Locations within which Anredera cordifolia is naturalised include southern Europe, southern and eastern Africa, temperate Asia, Australia, New Zealand, Mexico, Central America, southern USA and some Pacific islands.
Anredera cordifolia is invasive in parts of Kenya and Uganda where is has escaped from cultivation, is invasive in many cities and is invading woodlots and forests. It is known to be present in Tanzania but its invasive status is unknown (A.B.R. Witt pers. comm.).
Anredera cordifolia is a weed of forest gaps and margins, moist woodlands, bushland, riparian zones (banks of watercourses), waste areas, disturbed sites, gardens, parks, plantation crops (e.g. sugar cane) and roadsides in wetter temperate, subtropical and tropical regions.
A long-lived (perennial), twining or climbing plant growing over taller plants and trees up to 30 m tall.The stems are hairless (glabrous) and grow in a twining fashion. Younger stems are green or reddish in colour and round in cross-section. They become rope-like in appearance and turn greyish-brown in colour as they mature. Distinctive greyish-brown or greenish-coloured warty tubers (1-10 cm long, but usually 2-3 cm long) often form at the joints (nodes) along the older stems. These wart-like tubers are very characteristic.
The leaves are alternately arranged, slightly fleshy (semi-succulent) in nature, hairless (glabrous) and sometimes have a glossy appearance. They are borne on leaf stalks (petioles) 5-20 mm long and are more or less heart-shaped (cordate) or broadly egg-shaped with broad end at base (ovate). These leaves (2-15 cm long and 1.5-10 cm wide) either taper to a blunt point or have a somewhat rounded tip (acute or obtuse apex).
Plants produce masses of drooping flower clusters (6-30 cm long) which arise from the forks (axils) of the upper leaves. Each flower cluster (raceme) bears numerous small, white or cream-coloured, fragrant flowers (about 5 mm across). These star-shaped flowers have five 'petals' (sepals or perianth segments) and are borne on short stalks (pedicels) 2-3 mm long. They also have five stamens and an ovary topped with a three-branched style and three tiny club-shaped stigmas. The petals (2-3 mm long) are fleshy, persistent, turn dark brown or black in colour with age. This plant does not produce fruit in Africa.
Anredera cordifolia mainly spreads via large numbers of specialised aerial tubers that are produced along the stems. They are also spread shorter distances after falling off stems high in the canopy (by gravity) and can be transported downstream in floods. If fragments end up in waterways, they are easily transported to new locations in this manner. It also spreads vegetatively by tuberous roots and creeping underground stems (rhizomes).
In Kenya, Anredera cordifolia is sometimes confused with the indigenous Basella alba L in the family Basellaceae. B. alba also called the (vine or Indian spinach), is a soft twining long-lived (perennial) plant, with fleshy green stems that are often tinged brownish purple. B. alba is a medicinal and nutraceutical plant (it provides health and medical benefits) and is a common green vegetable in some parts of East Africa. The leaves of B. alba are also heart shaped with a pointed tip and shiny dark green and the flowers are similarly small, cream or white. The distinguishing feature is the presence of wart-like tubers in A. cordifolia and their absence in B. alba.
Anredera cordifolia has been spread around the world as an ornamental plant. However, this use cannot compensate for this plant's overall negative impacts.
It is most problematic in moist forests, rainforest margins and riparian zones (banks of watercourses); where it has the ability to establish under an intact canopy and can quickly engulf native species. The growth rate of stems in warmer and moister regions can exceed 1 m per week, and it can grow up to 6 m in a growing season. Its climbing stems can totally envelop the canopy layer, while is trailing stems also smother the ground layer of invaded habitats. This reduces light penetration, eventually killing the plants underneath and preventing the germination and regeneration of native plants. The sheer weight of dense infestations can even bring down trees in the canopy layer, and in this way A. cordifolia can change the structure of invaded communities, eventually destroying them. A. cordifolia is also suspected of poisoning livestock. It is poisonous and its sap is a skin irritant.
Because it quickly proliferates from small vegetative parts (its aerial tubers), and also survives by underground tubers, A. cordifolia is notoriously difficult to control. The tubers are often dispersed in dumped garden waste and contaminated soil which supplements natural dispersal.
A. cordifolia has been included in the Global Invasive Species Database (GISD 2006). It has been listed as an noxious weed in South Africa (prohibited plants that must be controlled. They serve no economic purpose and possess characteristics that are harmful to humans, animals or the environment), New South Wales and Queensland (Australia) and Hawaii.
The precise management measures adopted for any plant invasion will depend upon factors such as the terrain, the cost and availability of labour, the severity of the infestation and the presence of other invasive species. Some components of an integrated management approach are introduced below.
The best form of invasive species management is prevention. If prevention is no longer possible, it is best to treat the weed infestations when they are small to prevent them from establishing (early detection and rapid response). Controlling the weed before it seeds will reduce future problems. Control is generally best applied to the least infested areas before dense infestations are tackled. Consistent follow-up work is required for sustainable management.
The following account of A. cordifolia management is taken from the Rainforest Rescue site Madeira vine (www.rainforestrescue.org.au/blog/2008/07/23/managing-madiera-vine/). Once established Madeira vine is very difficult to control. The standard approach is to scrape long sections of the vines with a knife, from ground level up to head height, and immediately paint with neat glyphosate. Scraping of Madeira must be done gently to avoid severing the vine. Thicker vines should be scraped deep enough to expose the white fibrous core of the vine. The vines are either carefully scraped and painted between the attached tubers or the tubers are removed from the lower section of the vine before scraping and placed in a bag. Bagging prevents aerial tubers from being knocked to the ground where they will eventually start growing. A proportion of the aerial tubers above the scraping will then rot with the rest of the vine and the remainder will fall to the ground. Where dense tuberlings occur around the climbing vines it may be beneficial to spray these before treating larger vines to avoid damaging them by trampling. Otherwise time must be allowed for them to recover to a sprayable condition. Standard spray application is glyphosate at the rate of 1:50 with water (200mL glyphosate per 10l water) plus LI 700 5mL/L of mix. . When using any herbicide always read the label first and follow all instructions and safety requirements. If in doubt consult an expert.
The key ingredient for the management of Madeira Vine at any site is regular follow-up weeding. It is easy to treat a large area of canopy vines initially, whereas it is very difficult to maintain a treated area over time. Areas of dense ground layer infestation typically require as many as 6 follow-up treatments per year to prevent the vines from climbing. It is essential that there is a consistent reduction of tuber input on a site for long-term success. Subsequent weeding of an area must occur regularly enough to prevent underground tubers from re-sprouting vines that climb up to produce new aerial tubers. Removal of available climbing ladders such as cut stems of Lantana is beneficial.
Not listed as a noxious weed by the state or governments in Kenya, Tanzania and Uganda.
Global Compendium of Weeds. www.hear.org/gcw. Hawaiian Ecosystems at Risk Project. Accessed January 2011.
Henderson, L. (2001). Alien weeds and invasive plants. A complete guide to declared weeds and invaders in South Africa. Plant Protection Research Institute Handbook No. 12, 300pp. PPR, ARC South Africa.
Maundu, P. M., Ngugi, G. W. and Kabuye, C.H.S, .(1999). Traditional Food Plants of Kenya. National Museums of Kenya, Nairobi.
Rainforest Rescue. Managing Madeira Vine. Rainforest Rescue. www.rainforestrescue.org.au/blog/2008/07/23/managing-madiera-vine/. Accessed March 2011.
USDA Plants Profile. Anredera cordifolia (Ten.) Steenis. Heartleaf madeiravine. The Plants Database. plants.usda.gov/java/. National Plant Data Center, National Resources Conservation Service, United States Department of Agriculture, Baton Rouge, Louisiana, USA. Accessed 5 March 2011.
Wikipedia contributors. "Anredera cordifolia." Wikipedia, The Free Encyclopedia. Accessed January 2011.
Agnes Lusweti, National Museums of Kenya; Emily Wabuyele, National Museums of Kenya, Paul Ssegawa, Makerere University; John Mauremootoo, BioNET-INTERNATIONAL Secretariat - UK.
This fact sheet is adapted from The Environmental Weeds of Australia by Sheldon Navie and Steve Adkins, Centre for Biological Information Technology, University of Queensland. We recognise the support from the National Museums of Kenya, Tropical Pesticides Research Institute (TPRI) - Tanzania and Makerere University, Uganda. This activity was undertaken as part of the BioNET-EAFRINET UVIMA Project (Taxonomy for Development in East Africa).
BioNET-EAFRINET Regional Coordinator: email@example.com