The study was carried out in tropical natural forest of Sandaun Province and on New Britain Island, both Papua New Guinea. Two timber permit holders, namely Vanimo Forest Products Pty Ltd. (VFP), holder of Timber Permit TP10-8, and Stettin Bay Lumber Company Ltd. (SBLC), holder of Timber Permit TP14-52, agreed to host this study on forest harvesting operations in Papua New Guinea.
The study documents each phase of the forest harvesting system currently applied by the above-mentioned companies, and compares planning and implementation of harvesting operations in the field against relevant regulations as published in the Papua New Guinea Logging Code of Practice.
Data on felling operations were collected through work and time studies at both study sites, whereas data on extraction could be collected only at the VFP site in Sandaun Province. As one part of a postharvest assessment of environmental impacts, a survey of skidtrails was carried out at the study site in Sandaun Province.
Felling at both study sites was done with the companies' equipment by workers with limited knowledge of felling techniques. Fellers were hired in compliance with a requirement of the timber permit that members of the landowner clan must be given employment preference. On the extraction operations the skidding assistants were hired under similar conditions. Tractor operators, however, were permanent employees and who remain with the skidding crew even when the harvesting frontier moves to an area owned by another clan.
The time required to fell a single tree was greater on Set-up M38/SBLC (21.48 min) than on Set-up BL14/VFP (17.37 min) although the average stem volume was almost the same, 5.9 m3 and 5.8 m3 respectively. Differences in site conditions were identified as the primary cause of the difference in felling productivity at the two study sites. For the same reason, total felling and bucking production rates differed on the two sites (13.92 m³/h of workplace time at M38/SBLC versus 16.91 m³/h of workplace time at BL14/VFP) in spite of similar log volumes. The measured production rates are typical of those reported in the literature for felling and bucking by untrained workers in tropical forest.
Skidding time-study data were obtained for two sub-samples of logs on Set-up BL14/VFP. The average skidding time on Sub-Sample 1 was 16.28 min/log at a maximum skidding distance of about 500 m, compared to an average of 24.40 min/log on Sub-Sample 2 where the maximum skidding distance was 1,050 m and weather conditions were significantly more difficult. Average production rates for the two sub-samples were 20.51 m³/h of workplace time on Sub-Sample 1 and 13.28 m³/h of workplace time on Sub-Sample 2.
Investigation of timber losses revealed a significant potential for improvement, mainly in the felling operation, which accounted for about 90% of the total timber loss at study site BL14/VFP due to undiscovered decay prior to felling and stems split during felling. Total timber losses amounted to about 8.2% at the study site, or 1.57 m³/ha. This is a typical level of forest residues according to a survey of the literature on harvesting in tropical forests.
The forest area occupied by skidtrails amounted to only about 5% due to the hilly to mountainous terrain conditions in Set-up BL14/VFP. The machine operator had to make use of favourable terrain features such as ridges, and skidding of logs to the landing was generally carried out by retracing the path used to arrive at the felling site. However, the most striking fact noted during the skidding study was that only about 8% of primary skidtrails were planned, marked in the field, and approved through acceptance of the Set-up Plan by the Forest Authority's project supervisor. The remaining primary skidtrails were created in an ad-hoc way during the skidding operation.
In the project areas visited for this study, forest harvesting clearly has a significant impact on the social and economic lives of the local people. It is currently the basis for nearly all economic development in the project areas, and thus influences the changes that are underway in local lifestyles. Such changes occur as people in remote areas become exposed to towns by the road networks developed to support forest harvesting, and the money earned through employment and payment of timber royalties permits them to purchase goods rather than relying on the traditional subsistence economy.
The results of this case-study show that, although major steps are already being taken to foster environmentally sound forest harvesting through the introduction of the "Planning, Monitoring and Control Procedures for Natural Forest Logging Operations" under Papua New Guinea's Timber Permit system, and by implementing the PNG Logging Code of Practice, much remains to be done.
Although the regulations mentioned above stress the importance of planning and control of logging operations, experience during this study suggests that the value of comprehensive planning and control at all levels has not yet been fully recognised by the logging companies.
A general lack of supervision, both by company logging supervisors and by the Forest Authority's project supervisors, does not encourage loggers to implement new rules and regulations or to change their way of carrying out individual working tasks. A major limitation with respect to implementation of the Logging Code of Practice is the relatively low skill level of workers, particularly those involved in felling operations. Although the requirement to employ landowners is recognised as a way of giving landowners the highest possible participation in resource development, it is also necessary to train these workers in proper harvesting practices if environmentally sound forest harvesting is to be effectively promoted.
As previously mentioned, PNG has taken important steps in introducing the Planning, Monitoring and Control Procedures and the Logging Code of Practice. Now during the implementation phase it is important to recognise the importance of both harvest planning and logger training as integral to the effective implementation of these new regulations. On the one hand, the Forest Authority must endeavour to find the right balance between strict enforcement of rules and regulations, and the need for flexibility in recognising the difficult economic and environmental conditions under which the companies must operate. On the other hand, it is essential for the permit holders and their logging operators to recognise the value of comprehensive harvest planning and to invest in the workforce training and development that will be needed in order to make the plans fully operational.
Both the Forest Authority and the logging companies must become committed to the same overall goal, namely to promote the implementation of environmentally sound harvesting so that harvesting systems become fully compatible with the objectives of sustainable forest management.