Rubber trees - Native to the rainforests of the Amazon basin
16 July 2019 (21827 visits)The rubber tree (Hevea brasiliensis) is a deciduous species native to the rainforests of the Amazon basin and found in Brazil, Venezuela, Ecuador, Colombia, Bolivia and Peru. It is mostly encountered in lowland moist forest habitats, including disturbed forest, wetland areas, and forest clearings.
The rubber tree is fast growing. In its natural habitat, it is an emergent tree, soaring beyond the rainforest canopy to heights in excess of forty meters (130 feet). In the endless competition for sunlight that takes places in tropical forests, rubber trees will often be the first species to take advantage of a break in the forest canopy caused by the fall of another tree species.
Rubber trees have soft wood, with limbs that emerge high up the trunk to branch outwards. They produce pungent yellowish flowers and a capsule-like fruit, and can live for more than one hundred years. But of course, what makes rubber trees so special is the milky substance that emerges from them whenever their inner bark is cut into or damaged. It is this pure white latex that is the source of natural rubber.
Latex is a plant product composed of a complex mixture of substances, including resins, fats and waxes, suspended in a water-based medium containing salts, sugars, alkaloids, enzymes and tannins. Latex circulates within the tree via branching tubes which penetrate the tree’s plant tissue. When these tubes are damaged, cut into, or methodically “tapped”, the tree’s white latex will “bleed” from it.
Although it had been used by the Olmec, Maya and Aztec peoples hundreds of years earlier, latex was first described for science in 1735 by the French explorers and naturalists Charles-Marie de La Condamine and François Fresneau. But it was the English experimental chemist Joseph Priestley, famous for his work on gases, who gave it the name “rubber”, when he realized that it could be used as a pencil eraser.
For more than one hundred years, dating back long before the advent of plastics, latex has been harvested on a massive scale to produce the elastic substance we know as rubber. In our modern world, rubber is used to make tires for vehicles or mechanical parts for industry, as well as consumer goods such as shoes and toys.
A century ago, rubber was an entirely natural product, made from the latex produced by three species of trees found in the vast forests of the Amazon basin (Hevea brasiliensis, Hevea guyanensis and Castilloa elastica). Following the industrial revolution in 19th century Europe, demand for rubber for the manufacturing of water resistant coatings and car tires led to a rubber boom in places like Peru’s Madre de Dios region.
To this day, rubber is deemed to be a commodity of such global importance that it is included in the European Union’s list of critical raw materials, even as falling global prices, disease and climate change have begun to threaten the world’s supply of natural rubber.
The rubber boom in this part of Peru ended as suddenly as it had begun, when the British established rubber plantations in East Asia, using Hevea brasiliensis seeds taken from South America. With the collapse of the rubber industry in South America, the Madre de Dios region’s economic importance quickly declined. Today, the region relies upon other rainforest products, such as the brazil nut, and the growing boom in ecotourism, with travelers from all over the world coming to enjoy responsible tourism in some of the best conserved primary tropical forest ecosystems found anywhere in the Amazon basin.
