(Cryptostegia grandiflora and C. madagascariensis)
The Division of Forestry and Wildlife of the Hawaii Department of Land and Natural Resources has designated this species as one of Hawaii’s Most Invasive Horticultural Plants.
- Fast growing, climbing plant usually with pinkish-purple flowers (sometimes white to pink or light purple). Can also grow as a bush.
- Shiny, dark green leaves that are about 7 cm (3 in) long, with triangular, 10 cm long (4 in) seedpods that grow in wing-like pairs.
- Native to Madagascar, introduced to Hawaii as drought-resistant ornamentals.
- Grows over other plants and trees to 13 m (45 ft) high, smothering and killing other vegetation.
- Twines tightly around other plants and restricts their growth.
- Extremely poisonous: it contains cardiac glycosides, which interfere with heart operation in humans and animals when the plant is eaten.
- When the vine is dry, a powdery dust emerges and can cause violent coughing, swelling of the nose, and blistering of the eyelids.
- Contact with the plant’s milky sap can cause burning rashes and blisters.
- Each seedpod contains 340-840 seeds, silky hairs on seeds allow them to spread by wind and water, seeds are also known to float and survive for a month in salt water before being washed ashore to sprout.
- Introduced to Western Australia, now considered one of the 10 worst invasive plants.
- Big Island – Rubbervine is a BIISC early detection target species. BIISC is working to locate and control infestations. Property owners are encouraged to remove this plant (carefully). Cultivated sparingly in Kailua-Kona and Kawaihae from sea level to 2100′ in elevation. Also found naturalized in Kau, near Whittington’s Beach Park.