Common name:Rubber vine
Scientific name:Cryptostegia grandiflora
Alternative common names:
India rubber vine, Palay rubber vine, purple allamanda.
Rubber vine is a perennial woody climber or vine, which can also grow as a sub-shrub in open situations. It’s a highly invasive weed in semi-arid natural ecosystems, especially dry or monsoonal rainforest.
Where does this species come from?Madagascar
What is its invasive status in South Africa?NEMBA Category 1b
Where in South Africa is it a problem?Limpopo, Mpumalanga and North West Provinces.
How does it spread?It is scattered short distances from the parent plant by wind that catches the tufts on the seed ends, or longer distances by floating on floodwaters. Most seed remains viable even after the pods have floated on fresh or salt water for over a month, potentially leading to spread between catchments. Seeds can also be potentially spread by birds, or in mud attached to vehicles, machinery and animals.
Why is it a problem?Rubber vine smothers and kills native vegetation. It is a severe threat to biodiversity. It also severely threatens riverine vegetation, and can potentially displace the plants and animals that inhabit riverbanks, thereby affecting the water quality of streams. In addition, the vine exudes a poisonous, milky sap that is known to kill livestock and other animals that feed on the plant.
What does it look like?Leaves:- The leaves occur in pairs and are a glossy dark green in colour. They are oval-shaped with tapered ends (elliptical), 60–100 mm long and 30–50 mm wide. Flowers: - Flowers large and showy, white internally, pinkish-white to lilac externally; corolla funnel- or trumpet-shaped, 5-6 cm long, 5-8 cm diameter, with 5 pointed, broadly spreading lobes. Fruit/seeds: - Fruits (follicles) are large green pods, 10-15 x 3-4 cm, produced in pairs horizontally opposed and diverging from the tip of a short common stalk; sharply 3-angled and tapering to a long beak. The pod contains 200-350 large (5-10 x 1.5-3 mm), ovate, brown seeds with a tuft (coma) of long (19-38 mm), fine, silky-white hairs at one end.