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Recently felled rubber tree logs ready for processing

 

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Four year old rubber trees

 

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Rubber

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Young rubber trees.

Current day tapping done correctly.

Rubber trees begin to yield approximately 6 years after planting and continue to produce for approximately a further 26 years, at which point the latex production becomes uneconomic and the trees are felled and new trees planted.

Target annual latex yields vary, but generally a tree will yield approximately 4-5 kgs per annum. Factors that directly affect the yields include the quality of the tapping (including the accuracy of tapping angles), the age of the tree, the use of rain guards and the actual rain fall pattern.

The rubber estate of Vizara comprises 3,507 hectares of which 2,285 hectares are planted and a further 1,222 hectares unplanted. There are approximately 600,000 mature trees and 33,000 immature trees on the estate. The trees comprise Clonal GG2 trees and budded trees of a number of different variants.

Vizara employees approximately 1,300 employees in the three core operating stages of production being:
Tapping: the process of extracting latex by the controlled shaving at a specific angle of the bark of either half or one third of the circumference of the tree.

Latex collection: where the latex is collected by the tapper from the tapped trees and brought in for weighing. Thereafter, the latex is taken to the factory for processing; and

Factory processing: the process by which latex is processed into dried rubber bales. Vizara operates two factories, one producing Ribbed Smoked Sheets also known as RSS rubber. In this process the latex is diluted to 12.5% with water and coagulated using diluted formic acid to produce rubber sheets which are then dried at 60 degrees centigrade. The other factory which is modern and much larger produces what is called Technically Specified Rubber also known as TSR. The equivalent of TSR 5 is Vizara Block Rubber or VBR 5 produced from latex and VBR 20 the equivalent of TSR 20 from cup lumps.

The latex for the production of TSR is coagulated using formic acid but thereafter it is fed into a primary crusher, prebreaker and finally into a pelletiser. The rubber is then dried at 110 degrees centigrade and pressed into 35kg rubber blocks using a hydraulic baling press.

The other important activity on the estate is that of felling and replanting. Once a rubber tree reaches around 32 years of age, the bark will have been tapped to a height of 2.4m from the ground. The combination of declining latex production and more difficult higher tapping makes the tree unsuitable for further harvesting. At this point the tree must be felled and replanting must take place.

To support the replanting process Vizara has extensive nurseries. These nurseries are of critical importance to the sustainability of the estate. In a year Vizara [grows/clones] approximately 60,000 young trees which is more than is required for the company’s replanting programme.