Intercropping
rattan with
rubber and
other crops
Abdul Razak Mohd Ali is Director-General and
R.S. Raja Barizan is Research Officer, Forest
Silviculture and Management, Forest Research
Institute Malaysia (FRIM), Kepong, Malaysia.
In Malaysia, rattan species have been intercropped with rubber (Hevea brasiliensis) trees in either well-managed commercial rubber plantations or smallholdings and abandoned or semi-abandoned plantations. Rattan interplanting in well-managed commercial rubber plantations was established according to a concept similar to agroforestry, which was aimed at increasing the yield of land and supplementing the income of smallholders/rural people. The income was estimated to be more than sufficient to cover the costs of replanting rubber (Salleh and Aminuddin, 1986).
So far only three rattan species have been found to be suitable for growing under rubber in peninsular Malaysia: Calamus manan, Calamus scipionum and Calamus palustris. The techniques of planting C. manan under rubber trees have been well developed. The age of rubber trees at intercropping and planting densities per hectare are important factors that need to be determined before embarking on planting. Four- to seven-year-old rubber trees were found to be best for intercropping with C. manan.
Although intercropping rattan with rubber trees appears feasible, rattan should be viewed as a supplementary crop only. In the planning phase, rattan planting should be timed for harvesting when the rubber trees are reaching the stage at which they need to be replanted, i.e. at around 25 years of age. This would minimize the difficulties encountered during harvesting of rattan and prevent damage to the rubber tree that could occur if the cane is harvested earlier. A longer planting time would mean that the canes are allowed to reach maturity and are more suitable for commercial processing.
Different clones of rubber probably vary with regard to their suitability as support and shade trees because of differences in branching habits, maximum height attainable, strength of branches, adaptability to soil conditions and proneness to wind damage. Clones with low branches were found to be suitable for intercropping with rattan because rattan can easily climb on them (Aminuddin, Nur Supardi and Abd Ghani, 1991). Clones with high, strong branches are only suitable for supporting mature rattan, but can hold two to four rattan plants. No studies have been carried out to investigate whether latex production of individual rubber trees is affected by the presence of rattan plants.
With intercropping of rattan and rubber, some management problems can occur. Rattan can hinder tapping operations. The dense crown of rattan can prolong the drying of the boles of the rubber trees after rain. Rattan harvesting can damage the branches of the rubber trees as well.
Planting rattan under other crops such as oil-palm is still under investigation. The growth of six-year old C. manan planted under 13-year-old oil-palm at the Malaysian Palm Oil Board Paka plantation, in Terengganu, appeared good. Annual height increment was 1.5 m (Nur Supardi and Suboh, unpublished data). However, there are some management problems that have to be solved first. The rattan crown hindered the harvesting of oil-palm fruit bunches and, consequently, caused a drop in the quantity of fruits collected. When the oil-palm frond was pruned, the rattan crown fell to the ground, causing shoot damage.
The Forest Research Institute Malaysia (FRIM) is investigating rattan planting (C. manan and C. caesius) integrated with bamboo. Gigantochloa laevis was chosen as an alternative support tree for rattan. In the trial, rattan is treated as the main crop and the use of bamboo as a support tree is expected to ease rattan harvesting later. Such integrated planting should also increase land yield with harvests of bamboo shoots from the third year onwards, although the study needs to be monitored further before the suitability of G. laevis as a support plant can be established.
Bibliography
Aminuddin, M., Nur Supardi, M.N. & Abd Ghani, I. 1991. Rattan growing under rubber in peninsular Malaysia: status, problem and prospects. In S. Appanah, F.S.P. Ng and Roslan, eds. Malaysian forestry and forest products research. Proceedings of the conference. Kepong, Malaysia, Forest Research Institute Malaysia. p. 79-86.
Salleh, M.N. & Aminuddin, M. 1986. Rattan as a supplementary crop in rubber plantation. In C. Rajarao and L.L. Amin, eds. Proceedings of the Rubber Growers Conference, Ipoh, Malaysia, 20-23 October 1986. p. 261-273. Kuala Lumpur, Malaysia, Rubber Research Institute of Malaysia.
