Ficus elastica Notes

Ficus Elastica

• Also known as:
  • Rubber fig
  • Rubber bush
  • Rubber tree
  • Rubber plant
  • Indian rubber bush
  • Indian rubber tree
  • Rambung
• Not to be confused with the Rubber tree.
• A species of flowering plant in the family Moraceae.
• Native to eastern parts of South and Southeast Asia.
• Naturalized in:
  • Sri Lanka
  • West Indies
  • Florida, USA
• Not used in commercial production of natural rubber.

Scientific Classification

• Kingdom: Plantae
• Clade: Tracheophytes
• Clade: Angiosperms
• Clade: Eudicots
• Clade: Rosids
• Order: Rosales
• Family: Moraceae
• Genus: Ficus
• Subgenus: F. subg. Urostigma
• Species: Ficus elastica
• Binomial name: Ficus elastica Roxb. ex Hornem. (1819) - not Roxb. 1832, nor Roxb. 1814 (the latter not validly published).

Synonyms

• Ficus clusiifolia Summerh. 1929 not Schott 1827
• Ficus cordata Kunth & C.D.Bouché 1846 not Thunb. 1786
• Ficus elastica var. belgica L.H.Bailey & E.Z.Bailey
• Ficus elastica var. benghalensis Blume
• Ficus elastica var. decora Guillaumin
• Ficus elastica var. karet (Miq.) Miq.
• Ficus elastica var. minor Miq.
• Ficus elastica var. odorata (Miq.) Miq.
• Ficus elastica var. rubra L.H.Bailey & E.Z.Bailey
• Ficus karet (Miq.) King
• Ficus skytinodermis Summerh.
• Ficus taeda Kunth & C.D.Bouché
• Macrophthalma elastica (Roxb. ex Hornem.) Gasp.
• Visiania elastica (Roxb. ex Hornem.) Gasp.

Description

• Large tree in the banyan group of figs.
• Grows to 30-40 m (100-130 ft) tall, rarely up to 60 m or 195 ft.
• Stout trunk up to 2 m (6 ft 7 in) in diameter.
• Develops aerial and buttressing roots to anchor it in the soil and support heavy branches.
• Broad shiny oval leaves:
  • 10-35 cm (4-14 in) long.
  • 5-15 cm (2-6 in) broad.
  • Largest on young plants (occasionally to 45 cm or 17 + \frac{1}{2} in long).
  • Much smaller on old trees (typically 10 cm or 4 in long).
• Leaves develop inside a sheath at the apical meristem, which grows larger as the new leaf develops.
• When mature, leaf unfurls and the sheath drops off.
• Another immature leaf is waiting to develop inside the new leaf.
• Dense canopy.

Pollination and Fruiting

• Flowers require a particular species of fig wasp for pollination (co-evolved relationship).
• Does not produce colorful or fragrant flowers to attract other pollinators.
• Fruit:
  • Small yellow-green oval fig.
  • 1 cm (\frac{1}{2} in) long.
  • Barely edible.
  • Fake fruits containing fertile seeds only in areas where the pollinating insect is present.

Range

• Natural range: Nepal, Indonesia, Bhutan, Northeastern India, Bangladesh, Myanmar, Thailand, Yunnan (China), and Malaysia.
• Widely introduced in most tropical regions, including Hawaii and the West Indies.
• In Europe, found in mild locations throughout the Mediterranean Basin.

Cultivation and Uses

• In parts of India, people guide the roots of the tree over chasms to form living bridges.
• Large bridges woven from aerial roots exist in Meghalaya, India.
• Aerial roots can be found on F. elastica as small as 1 feet tall.

Latex

• All parts of the plant contain abundant milky white latex.
• Latex is a chemical compound separate from its sap, carried and stored in different cells (laticifers).
• Latex can irritate the eyes and skin and is toxic if taken internally.
• Sap can be used to make rubber.
• Once the most common plant in Sumatra and Malay Peninsula for tapping before the Pará tree (Hevea brasiliensis) was introduced from Brazil in the late 1800s.
• Rambung trees were valuable to farmers in Aceh.
• Latex has been tested for use in the manufacture of modern rubber, but without economic and technical results.

Ornamental

• Grown around the world as an ornamental plant.
• Outside in frost-free climates (tolerates light frosts) from the tropical to the Mediterranean.
• Inside in colder climates as a houseplant.
• Thrives in USDA hardiness zones 10-12.
• Prefers bright sunlight but not hot temperatures.
• High tolerance for drought, prefers humidity, and thrives in wet, tropical conditions.
• Ornamental hybrids (e.g., Robusta) have broader, stiffer, and more upright leaves than the wild form.
• Many hybrids exist, often with variegated leaves.
• Most cultivated plants are produced by vegetative propagation (cuttings or layering).