Taxonomic name: Cryptostegia grandiflora (Roxb. ex R. Br.) R. Br.
Synonyms: Nerium grandiflorum Roxb. ex R. Br.
Common names: caucho de la India (Spanish-Galapagos), India rubber vine (English), liane de gatope (French- New Caledonia), palay rubbervine (English), purple allamanda (English), rubber vine (English)
Organism type: vine, climber Cryptostegia grandiflora is a self supporting, many-stemmed vine that is capable of growing over trees up to 15m high, smothering and pulling them down. It occurs in dry and moist forests in disturbed situations where there is temporary or permanent water, such as in rainforest openings and along roadsides. C. Grandiflora is poisonous to stock when consumed and it forms impenetrable thickets that may restrict stock access to water. It decreases water catchments due to increased transpiration resulting in a loss of trees and native vines, which in turn leads to a loss of biodiversity and habitat. Description
Rubber vine, Cryptostegia grandiflora, is a self supporting, scrambling, many-stemmed vine that grows to 2 metres tall with long trailing whips. A milky sap oozes from stems, leaves and seedpods when cut or broken. Leaves are dark green and glossy, 6-10cm long, 3-5cm wide and in opposite pairs. Roots have been found at a depth of 13 metres in mine shafts. Roots of seedlings are twice as long as shoots. The growth form of rubber vine differs depending on the surrounding conditions. They can form dense canopies of overpapping plants with long whips, form towers upto 30mts high the height of native trees and grow as freestanding shrubs in the absence of other vegetation.Flowers are large and showy, with five white to light purple petals in a funnel shape. The seedpods are rigid, 10-12cm long, 3-4cm wide and grow in pairs at the end of a short stalk (Agriculture and Resource Management Council of Australia and New Zealand).The flowers resemble those of the purple Allamanda (Allamanda violacea)" (PIER, 2003). Occurs in:
agricultural areas, natural forests, planted forests, range/grasslands, riparian zones, ruderal/disturbed, scrub/shrublands, water courses, wetlands Habitat description
Dry forest, roadsides, moist forest, rainforest openings at low elevations, (PIER, 2003). An aggressive woody climbing shrub which is capable of growing over trees up to 30m high, (PIER, 2003). "Plants are common in disturbed situations where there is temporary or permanent water, such as along gullies, rivers, creeks, waterholes and in saltmarsh areas.” (Marohasy and Forster, 1991. In PIER, 2003) General impacts
C. grandiflora is poisonous to stock when consumed and its rampant growth may restrict stock access to water points, (WA, Department of Agriculture). It damages the environment by smothering and pulling down riverside vegetation, (WA, Department of Agriculture). C. grandiflora forms impenetrable thickets and smothers vegetation; reduces productivity and pasture production; if eaten it can lead to cattle deaths; leads to decreased water catchment due to increased transpiration; results in a loss of trees and native vines, which in turn leads to a loss of biodiversity and habitat, (CSIRO Australia, 2001). In the open, Cryptostegia grandiflora forms impenetrable thickets, (PIER, 2003). Notes
A major environmental weed of central and northern Queensland, Australia and invasive in the Virgin Islands, (PIER, 2003). Geographical range
Native range: Madagascar.
Known introduced range: Commonwealth of the Northern Mariana Islands (Saipan), Cook Islands (Rarotonga, ‘Atiu, Mangaia, Penrhyn (cult.)), Fiji, Guam, Hawai‘i, Marshall Islands (Kwajalein (cult.)), New Caledonia (Voh, Gatope). Australia, Southeast Asia, Mauritius. Reported to be present by the Cook Islands Natural Heritage Project. Introduction pathways to new locations
Agriculture: Introduced for cultivation in India to produce a poor quality rubber latex, (WA, Department of Agriculture).
For ornamental purposes: Initially introduced to Australia as an ornamental species, (CSIRO Australia, 2001).
Ignorant possession:
Internet sales/postal services: http://www.rareflora.com/cryptostegiagran.htm
Road vehicles (long distance):
Transportation of domesticated animals:
Local dispersal methods
Agriculture (local):
Escape from confinement: Escaped from cultivation, (WA, Department of Agriculture).
For ornamental purposes (local): Cultivated as an ornamental plant because of its showy flowers and hardiness, (WA, Department of Agriculture).
Off-road vehicles:
On animals: Seeds may be carried longer distances by stock, (WA, Department of Agriculture).
On animals (local): Seed have long silky hairs allowing them to be carried short distances by the wind, (WA, Department of Agriculture).
Translocation of machinery/equipment (local): Seeds may be carried longer distances by vehicles or machinery, (WA, Department of Agriculture).
Water currents: Seeds can float in salt water for up to 40 days, and may still remain 60% viable after this. Management information
Preventative measures: A Risk assessment of Cryptostegia grandiflora for Australia was prepared by Pacific Island Ecosystems at Risk (PIER) using the Australian risk assessment system (Pheloung, 1995). The result is a score of 16 and a recommendation of: reject the plant for import (Australia) or species likely to be a pest (Pacific). Nutrition
Prefers high levels of soil moisture for rapid growth, and subsequently is often found bordering rivers, (WA, Department of Agriculture). However roots have been known to grow up to 13m deep allowing growth even in arid conditions. Reproduction
Wind- and water-dispersed seeds. Seeds form in large pods about 15cm long which are often found in pairs, joined at the base. Each pod contains numerous seeds, each seed has a tuft of long white silky hairs. (WA, Department of Agriculture).
It can produce more than 8000 seeds in a single reproductive episode and can set seed at least twice per year. More than 90% of seeds will germinate within 10 days of moisture becoming available (Grice 1996). Each seed pod produces 340-840 seeds, and seeds can float in salt water for up to 40 days, and may still remain 60% viable after this. Lifecycle stages
Few seeds last more than 12 months in the soil (Grice, 1996). Plants begin reproducing at about 200 days (CSIRO Australia, 2001). Reviewed by: Dr Wayne Vogler. Weed Scientist Tropical Weeds Research Centre, Dept. Natural Resources and Mines, Queensland Australia
Compiled by: IUCN/SSC Invasive Species Specialist Group (ISSG)
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Last Modified: Friday, 30 December 2005
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