LIPA ANAK AKENG¹

A study of termite species that often attack buildings and timber was carried out for the first time at Similajau National Park. Thirty one timber buildings were surveyed, nine (29%) of which were attacked. Two types of damage were recorded: defacement and cavitation. The termites found were from the genera Cryptotermes, Nasutitermes, Coptotermes and Amitermes. Many types of timber were attacked, including belian (ironwood).

INTRODUCTION

Termites form part of the natural forest ecosystem, living in the forest floor and decomposing leaf litter and fallen branches. They become pests when they attack buildings or crop trees. There are three common families of termites found in Sarawak: Kalotermitidae (dry-wood termites), Rhinotermitidae and Termitidae (both wet-wood termites). Termites are social insects and develop large colonies in nests in the soil. The biggest termite nest ever found was built in Borneo by Macrotermes sp. (Thapa 1980). They build ‘galleries’ made of soil between their nest and their food source; these galleries from the soil to the posts and beams of buildings are the signs of termite attack.

Timber is widely used in National Parks for buildings and other structures, but no study has ever been made of the effects on termites on park buildings. The only work that has been done is by the Timber Research and Technical Training Centre, which buried specimens of different timber species at a site in Bako National Park.

This study looked for termite attacks in the buildings at Similajau National Park, to record the extent of attacks, the species of termites, and the timber species attacked.

There is no record of soil treatment before the construction of any buildings at the Park. Some of the timber used for construction had been treated with creosote. City Pests Specialist Resources had carried out termite treatment of all buildings in November 2000, but no information about the termiticide used was available.

All 31 buildings on the site were surveyed. Termite specimens were preserved in 40% alcohol and sent to the Forest Research Centre in Kuching for identification (carried out by Abdul Rahman Osman).

Nine of the 31 buildings had been attacked, by six species of termites in four genera: Cryptotermes (Kalotermitidae); Coptertermes (Rhinotermitidae); and Nasutitermes and Amitermes (both Termitidae). Details are given in the Appendix.

No termite attacks were found on timber which had been treated with creosote.

Termite damage was found to be quite extensive, affecting 30% of the buildings on the site, and included both surface defacement and internal cavitation. Most types of timber were affected, from plywood, through meranti, white meranti and selangan batu to belian (ironwood).

Termite attacks often started from the soil or from tree branches touching the building. Dead wood, tree stumps and nearness to forested areas also increase the likelihood of attack. When forest is cleared for building, dead wood should be removed and not left to rot under the building; beams should not be supported on old stumps. Tree branches should be pruned back so that they do not touch buildings.

As noted, timber treated with creosote was not attacked; treatment with creosote should be carried out thoroughly for all buildings close to forested areas or which are close to the ground. However, treatment with other chemicals was not effective, including the treatment by City Pests Specialist Resources. Since creosote cannot be used on all timbers (furniture, for example), alternative treatments should be tried out. Since this study was completed, the Forest Research Centre, Kuching, has treated all buildings with ‘Termiticide 40’, and the results will be monitored.

Termite damage can be extensive and can be expensive to repair. Simple precautions before construction can reduce the risk, and maintenance routines should include pruning trees back from buildings and checking for galleries on posts.

Treatment with creosote appears to be effective, and the results of using different chemicals should be monitored and the cost-effectiveness of treatment by the Forest Research Centre and private firms compared.

REFERENCE

Thapa, R S (1980) Termites of Sabah, Chin Chi Printing Works, Kota Kinabalu

APPENDIX. Termite attacks on buildings at Similajau National Park