Unformatted text preview: gs were sent, in Wardian cases, to Ceylon, and 22 were sent to the Botanic Gardens in Singapore. Once established outside its native country, rubber was extensively propagated in the British Brazil provided the world with the rubber tree, Hevea Brazil provided the world with the rubber tree, brasiliensis, but that country no longer plays any significant part in the world natural rubber trade. Seeds were exported from the lower Amazon area of Brazil to London by Henry Wickham, a local planter acting for the British Government in 1876. The seeds were germinated at the Tropical Herbarium in Kew Gardens, London later that year. From there seedlings were exported to Ceylon (now Sri Lanka). In 1877, 22 seedlings were sent from Ceylon to Singapore, where they grew strongly, and the technique of tapping was developed. Hevea brasiliensis Seeds
Hevea brasiliensis Prior to this, the trees had to be felled before the Prior to this, the trees had to be felled before the latex could be extracted (slaughter tapping).
By 1900, most of the techniques and agricultural practices required to establish large plantations had been developed. One key technique was bud grafting. This is essentially a cloning technique which ensures that genetically identical trees can be produced in unlimited numbers.
The rubber industry often talks about high
yielding clones, or other types of clones; and this is the basis of that terminology. T or Shield Budding T or Shield Budding Over the next 40 years, the British in Malaysia Over the next 40 years, the British in Malaysia and the Dutch in Indonesia cleared large areas of rainforest to create rubber plantations. Simultaneously, local farmers saw the opportunities of rubber cultivation, and planted small groves of trees to supplement their own income. This gave rise to two types of rubber plantations in most producing countries: the estates and the smallholdings. Smallholdings tend
to produce solid rubber while estates are essentially largescale farms, with professional management. Most latex comes from The tree can reach a height of 90 feet. The white The tree can reach a height of 90 feet. The white or yellow latex occurs in latex vessels in the bark, mostly outside the phloem. These vessels spiral up the tree in a righthanded spiral which forms an angle of about 30 degrees with the horizontal. Once the trees are 56 years old, the harvest can begin: incisions are made at right angles to the latex vessels, just deep enough to tap the vessels without harming the tree's growth, and the sap is collected in small buckets. This process is known as rubber tapping. Older trees yield more latex, but they stop producing Rubber tree bark has several layers. One Rubber tree bark has several layers. One of these...
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- Fall '11
- Rubber, Natural rubber