Rubber vine (Cryptostegia grandiflora) is a highly invasive perennial woody shrub or vine that is widely distributed throughout tropical and subtropical regions worldwide. C. grandiflora can grow unsupported 1-2 m high, or it can scramble up to 30m high in trees. It has grey-brown stems that are covered in raised spots. C. grandiflora leaves are thick , leathery, glossy dark green on the top surface and pale and dull on the bottom. The stems, leaves and unripe seed pods exude a white, milky sap when broken or cut.
C. grandiflora flowers primarily in the summer, producing white, purple or pink colored tube-shaped flowers. Green or brown pairs of pod-like fruits containing flat brown seeds are formed between the summer and late autumn months.
Toxic components
All parts of
C. grandiflora contain cardiac glycosides. Cardiac glycosides inhibit the cellular Na+/K+-ATPase which enhances cardiac inotropy (contractility) and slows the heart rate.
- weakness
- diarrhea
- cold extremities
- blue-purplish comb
- difficulty breathing
- sudden death
MANUAL CONTROL: Rubber vine can be effectively controlled by burning. Two successive annual burns are recommended.
MECHANICAL CONTROL: For scattered or medium-density infestations, slashing the vines close to ground level is found to be effective. For dense infestations, during the winter, stick-raking or blade-ploughing reduces the bulk of the infestation. Pasture should be sown and windrows burned to kill residual seed. Follow-up treatment is essential.
CHEMICAL CONTROL: Rubber vine can be effectively controlled with herbicides. Aerial application, foliar spray, basal bark spray, cut stump treatment, and soil applications.
