Several approaches, techniques and systems were developed in the 80s and 90s to tackle the problem of tapper shortage and rising costs of production, which were not adopted on a large scale due to low productivity of prevailing clones in the 80s/90s, very low selling prices of rubber, low wages paid to tappers, lack of potent methods of yield stimulation and poor demand for speciality grades.
The change in scenario today has made these approaches and techniques more attractive, namely the high productivity of modern clones, very acute shortage of tappers, reasonable selling prices of rubber, high wages paid to tappers, availability of potent methods of stimulation and the bulk of rubber traded are speciality grades.
The percentage breakdown of total cost of production of one kilogram of rubber in Malaysian plantations shows that the direct cost of field upkeep and cultivation is 7 percent of the total cost, direct cost of tapping and collection is 61 percent of the total cost and the indirect cost is 32 percent of the total cost.
The indirect cost is made up of managerial and staff salaries, maintenance cost of buildings and factory, depreciation of building and other fixtures, fees, rents insurance and others. The direct cost of upkeep and cultivation is made up of 4 percent for manuring, 4 percent for weeding and 2 percent for control of pests and diseases.
The breakdown of the direct costs of tapping and collection is made up of 83 percent for tapping and collection, 2 percent for stimulation and 5 percent for transport of crop to the factory.
Enlarged task sizes of 700, 800 and 900 trees
Data available shows that for a field of 100 hectares, the land : man ratio can be increased from six hectares per tapper to nine hectares per tapper by increasing the task size from 600 to 900 trees. The tapper requirement can be reduced from 17 to 11 tappers for 100 hectares in tapping or a 35 percent reduction in tappers. There is a payment of task bonus for task sizes above 600 trees as per the management/workers wage agreement.
Key findings from studies carried out on enlarged task tapping by the Rubber Research Institute of Malaysia are that the tapping time for 900 trees increased by 29 percent (5.35 to 6.94 hours), number of trees tapped per hour increased from 177 to 204 trees, the work speed of the tapper (seconds per tree), which covers tapping, walking and slack time, was reduced from 20.4 to 17.6 seconds, tappers wages increased by 53 percent, no tapper fatigue though there was some stress in collection, no depression in yields if tapping completed by 11:30 a.m. in the morning and 103 percent increase in tapping margin (gross revenue minus tapping/collection costs).
Enlarged task tapping (750 trees per task) in combination with polybag collection of poly lumps once in two weeks showed an increase in yield per tapping of 64 to 124 percent, tapper requirement reduced from 480 to 274 tappers (33 to 50 percent), tapping/collection costs reduced by 11 percent, tapping wages increased from 45 to 99 percent and transport costs reduced by 37 percent for transport of poly lumps as opposed to transport of latex.
Division of labour
This approach involves separation of functions of tapping and crop collection with the latter handled by unskilled workers in the plantation. In the Dolcup system the tapper taps an extended task (E-Task) of between 950 to 1200 trees with crop collected daily as latex by collectors who are unskilled workers.
In the Dolbag system the tapper taps an E-Task (950 to 1200 trees), while the crop is collected as poly lumps in polybags once in two to three weeks by unskilled workers. For the Dolcup system the tapper is paid a basic wage plus 70 percent incentive above 22 kg and 70 percent of scrap payment, while the collector is paid a basic wage plus 30 percent of incentive above 22 kilograms and 30 percent of scrap payment.
For the Dolbag system the tapper is paid a basic wage plus 100 percent of polylump incentive above 11 kg, while the collector is paid a basic wage plus overtime. The Dolcup and the Dolbag systems are now more attractive for adoption with use of more potent stimulation system such as the RRIMFLOW system because it will ensure higher incomes for tappers with tapping of E-Tasks and tappers reluctance overcome with marked increase in incomes.
The reduction in tapper requirement for Dolcup and Dolbag systems for a field of 100 hectares indicates that the land : man ratio for both Dolcup and Dolbag systems increases to 12 hectares per tapper while the percentage reduction in tapper requirement is 50 percent. There is a need for unskilled workers for crop collection. Field workers who handle unskilled jobs in the plantation such as weeding can be used for the crop collection.
Once a week tapping system
The once a week tapping system is adopted either with Ethephon stimulation or RRIMFLOW stimulation. Fields tapped with RRIMFLOW stimulation can be combined with enlarged task sizes. The land : man ratios for once a week tapping plus normal tasks (600 trees) is 12 hectares/tapper, 16 hectares/tapper with enlarged task size of 800 trees, 24 hectares/tapper for E-Tasks (1200 trees) and 15 hectares for once a week tapping of short cuts on high panels in combination with enlarged task size of 850 trees.
The tapper requirement for once a week tapping plus normal tasks is reduced by 50 percent when compared to 1/2s d/3 tapping plus normal task, once a week tapping plus enlarged task (800 trees) reduced by 65 percent, once a week tapping plus E-Task (1200 trees) reduced by 75 percent and once a week tapping on short cuts on high panels plus enlarged task (850 trees) is reduced by 60 percent.
However, to realize reasonable yield productivity per hectare in fields tapped on once a week tapping system requires very potent methods of stimulation such as the RRIMFLOW system. The once a week tapping system in combination with RRIMFLOW stimulation is an economically viable system to overcome the problem of acute shortage of tappers.
The once a week tapping system (1/8s^ d/7) in combination with RRIMFLOW stimulation has been adopted on 1000 hectares planted with six different clones (tapped on high panels) in a plantation with acute shortage of tappers and where the fields had not been tapped for more than a year. The system was implemented in combination with enlarged task size of 850 trees with cup lump collection in 1.5 litre capacity latex cups once in two to three tappings.
The tapper requirement was reduced from 103 tappers to 69 tappers (33 percent reduction) and land : man ratio increased from 9.7 hectares per tapper to 14.5 hectares per tapper relative to conventional tapping on 1/4s^d/4 plus Ethephon stimulation in combination with normal task size of 600 trees.
Data available shows that with exception of two clones PB 235 and AVROS 2037 the yields of all the other clones ranged from 2274 kg/ha/yr to a high of 3017 kg/ha/yr. It is apparent that the once a week tapping system on short cuts in combination with RF stimulation is a very viable system for realizing high yield productivity per hectare while overcoming the problem of acute shortage of tappers.
High density planting
Data available from high density trials shows that the tree productivity decreases as the density of planting increases irrespective of the panel in tapping. The drop is more marked as the density is increased from 211 trees/ha to 557 trees /ha with decline thereafter less marked when density is increased to 741 and 1067 trees per hectare. However, for land productivity (kg/ha/yr) there is a progressive increase with increase in density of planting though the increase levels off after a density per hectare of 741 trees.
Data obtained on tree and land productivity in fields planted with normal density (450 to 480 trees per hectare) and tapped on once a week tapping system plus Ethephon stimulation in combination with normal task size (550 to 600 trees) shows as given that the tree productivity is very high ranging from 76.1 g/t/t for clone PR 261 to a high of 134.3 g/t/t for clone PB 260. However, the land productivity in contrast is low ranging from a low of 1191 kg for clone PR 261 to 1735 kg /ha/yr for clone PB 260.
Yield projection data shows that when the density of planting is increased to between 600 to 700 trees per hectare at time of planting and these fields than brought into tapping on once a week tapping system it would be possible to trees productivity levels of 80 to 90 grams per tree per tapping and land productivity levels of 2106 to 2288 kg /ha/yr. These projected land productivity levels will be much higher if the once a week tapping system is combined with RRIMFLOW stimulation.
In the future due to the prevalent challenges faced by the rubber industry it would be prudent to increase the density of planting for fields being replanted or for new plantings and then target these fields for once a week tapping plus Ethephon or RRIMFLOW stimulation in combination with enlarged task sizes. This would be one practical approach to resolving the problem of acute shortage of tappers while not compromising the yield productivity and hence the profitability per hectare.
If rubber plantations are to remain economically viable and sustainable over the long term, they have no choice but to opt for the systems and approaches described in this article. (Reference: Dr. S. Sivakumaran Executive Director Research and Development, Greenyield Berhad, Malaysia)
(N. Yogaratnam can be contacted at firstname.lastname@example.org)