Another wage hike:

What should be the next move in rubber plantations?

by Dr. Lakshman RODRIGO

Wage hikes are inevitable. As we all know, wages in the plantation sector have recently increased by about 27 percent; from Rs. 405 to Rs. 515 per day.

Dr. Lakshman Rodrigo

With EPF and ETF contributions, the total is Rs. 572 a day. This has an effect on other terminal benefits such as gratuity. Continuous increase in cost of living associated with the inflation drives people to demand for high wages.

Due to the improvements in science and technology together with striking advertisements, people are attracted to new luxuries; another reason to demand high wages.

In the past, plantation workers were considered to be a underprivileged category in a society. It is no more and it should not have been so; being involved in key economic activities, their contribution to the nation building is second to none.

They are covered and protected by strong trade unions supported by parliamentarians. This has strengthened their bargaining power and so, no way to ignore their demands. Recognising the needs and importance of this sector, the present government has taken steps to provide them good educational and health facilities.

As a way of improving the social dignity, official designations given to plantation workers have recently been changed with a special gazette notification. Nonetheless, some have already taken their move to work in other sectors for greener pastures.

Whilst meeting the worker needs, plantations should maintain their financial viability under any circumstances. Undoubtedly, current prices for raw rubber can cope up with recent wage increase in rubber plantations.

Although there is no speculation on market collapse, we need to be proactive to sustain rubber plantations for the future. Competitiveness would be the best approach for the sustainability. Particularly in human resource management, worker use efficiency and worker satisfaction / motivation are key issues to be tackled.

Cost of Production

Cost of Production (COP) generally declines with increase in worker-use efficiency.

Nevertheless, it is not always the case in the competitive market since workers are to be motivated with improved wage structures. Unlike in the past, managerial staff in most of Regional Plantation Companies (RPCs) has been reduced to bear minimum with given added facilities.

Unfortunately, no such move for worker class. All activities are important, however the first priority should go to what requires most labour. In rubber plantations, latex harvesting is labour intensive utilising over 60 percent of the workforce. In COP, its share is well over 1/3. Therefore, it's time to revise our harvesting policies in rubber estates for improved worker-use efficiency. Latex is usually harvested from rubber trees by tapping the tree trunk with a half spiral cut (i.e. half of the circumference) once in two days.

This is called S/2 d2 harvesting (S/2 stands for half spiral cut and d2 for once in two days). Each harvester is given about 300 trees per day hence 600 trees in two day cycle.

This means an area having 600 trees require a harvester every day. Rubber is planted at a density of 515 per hectare, however it diminishes to some extent with time.

Expecting an average about 400 trees in tapping per hectare, worker requirement for harvesting of mature rubber is about 0.6 per hectare per day.

This is just second to tea and coconut needs only about 0.2 per hectare per day. What can we do about this? All attempts made so far to mechanise rubber harvesting had no success and there is no sign of being a reality even in near future. So, waiting for latex harvesting machines would not be a wise decision. What is next? Is it necessary to tap the rubber tree so often? Is there a way to get the latex out with less labour?

Alternative methods

Low Intensity Harvesting (LIH) systems are found to be the most appropriate means to increase the worker use efficiency in latex harvesting. What does it mean by LIH? When compared with the previously mentioned traditional S/2 d2, either harvesting frequency or tapping cut length or both are reduced in LIHs.

Reduction in the harvesting frequency is made by extending the time gap between two consecutive harvesting over two days and commonly named as Low Frequency Harvesting (LFH).

Instead of half spiral, attempts have been made to reduce the cut length to quarter spiral or even less.

As everyone would expect, reduction in harvesting frequency and cut length has a negative impact on latex yield.

To compensate the yield loss associated with this reduced intensity, yield stimulants are to be applied in a judicious manner. Ethylene is the ultimate stimulant which enhances latex production in the laticiferous system in the rubber tree bark. Obviously, outside application of ethylene gas is not simple and so, ethephon is generally used as a liquidised paste in different formulations to facilitate a slow release of ethylene inside the bark. It is available in the market under different trade names (e.g. Ethrel, Ethephon Plus).

In the past, latex yield stimulants were used to increase yields. This has been a wrong intention and today, it remains as a short-term approach perhaps suitable for the rubber fields at the verge of uprooting.

In the long-run, the potential yield of the rubber tree cannot be exceeded in harvesting. Perhaps, you may have planted a rubber clone having a high genetic potential for high yields. However, the way you have looked after the rubber field determines the ultimate yield potential. It is similar to bringing up a child. Though genetically sound, final outcome depends on the nutrition, guidance, education and diseases .

Studies have shown that overharvesting with stimulants results in yield decline in subsequent years and also, leads to physiological disorders such as Tapping Panel Dryness (TPD) where latex synthesis in the bark ceases.

Therefore, ethephon is used in LIH to obtain the potential yield in other words, only to compensate the yield loss due to reduction in harvesting frequency or cut length or both.

As a rule of thumb, we could consider the yield given by time-honoured S/2 d2 as the potential. To overcome the time related discrepancies associated with harvesting frequency, average yield per tree per year (YPT) or yield per hectare per year (YPH) could be taken for comparison.

How does LIH increase the worker-use efficiency and is it the only advantage? Apparently, we could expect a four-fold benefit from LIH; firstly worker-use efficiency. With the increased time gap between two harvestings, each harvester can be allocated to a greater number of tapping blocks resulting in reduced harvester requirement.

For instance, if trees are tapped once in three days instead of two-day intervals, worker requirement is reduced by 1/3; if four day intervals, four blocks to each harvester hence reduction is 50%. Even with the reduction of tapping cut length, there is a time saving; hence number of trees allocated to each tapping block could be increased. It is expected to increase the tapping block size from 300 to 400 trees with a reduction of tapping cut length from half to quarter spiral; 25 percent reduction in labour use.

To be continued

The writer is the Head of the Department of Biochemistry and Physiology, Rubber Research Institute of Sri Lanka.