Traditionally, timber harvesting operations in the Philippines were based on a system of manual felling and bucking, with the use of water buffalo or gravity for land transport, and water transport for longer distances. These practices were mostly based on shortwood methods, where trees were cut into lengths which could then be handled by man or animal power. Such practices were used all over Southeast Asia for centuries. Tree felling was mostly done with axes, machetes, or jungle knifes. These techniques were normally environmentally sound, and caused only minor damage to residual stands and soils and minimal disturbance of biodiversity.
In the 1920s, two-man raker tooth saws replaced axes in felling and crosscutting operations. In the early 1960s, crosscut saws were in turn replaced by power chainsaws, and a new era in safety and ergonomics began. The problems of noise pollution and vibration became a concern.
Cable harvesting systems were originally introduced to the Philippines from North America. Under these systems, trees are delimbed and topped, after which the stem is dragged to the road by cable. Normally tree-length logs are transported, but in the case of very large trees, the stem is crosscut into two or more logs, depending of the diameter of the trunk.
A main objective of cable systems is to reduce the need for road construction. By using this method, it is also possible to minimize soil erosion associated with roads. The usual technique in cable harvesting is to lift one end of the log in the air and drag it from the felling site to the road or landing.
The cable harvesting systems introduced in the Philippines after 1945 were the so-called "highlead" type. These systems lift only one end of the log into the air, while the major part of the stem is dragged along the ground. These harvesting systems were originally developed and adapted for the temperate and boreal northern forest soils with only moderate rainfall, and ground surfaces which are often frozen or snow-covered. In introducing these systems to the Philippines, little thought was given to their suitability in areas of high rainfall and soft soil.
The Philippine forests were harvested by these technologies for more than 35 years. With the drastic reduction of natural forests, however, the highlead systems became unacceptable. The adverse environmental impacts were finally recognized as very severe. Damage to the forests could be seen everywhere. After logging, the badly torn forest landscape threatened not only the biodiversity of plants and animals, but also the livelihood of forest dwellers. In 1980, due to the obvious damage in the logged-over forests, legislation was passed reducing the maximum horse power allowed in cable harvesting operations in natural forests.
By 1980, the government plantations in the Philippines should have been quite extensive, since between 50,000 and 100,000 ha had been planted annually for many years. However, many of these plantations had been destroyed or severely damaged. The government therefore was discouraged from developing harvesting technologies for plantations since few of the remaining government plantations required thinning or harvesting.
Fortunately, the efforts of ILO, FAO, the Asian Development Bank (ADB), and USAID in promoting plantation forestry resulted in a budding interest within the private sector for developing appropriate technologies for plantation-grown wood. The southern, and particularly the southeastern, part of the Philippines thereafter became the main focus in the development of plantation forestry, with a large number of people growing trees on their own land.
In 1976 and 1977, an ILO/Finland project, implemented in cooperation with the Bureau of Forest Development (BFD), sought to develop appropriate technologies for manual harvesting of plantation trees in the southern Philippines. The core project had two sites, one in Tuñgao and the other in the Bislig Bay area, extending in a radius of approximately 120 km from each of the two towns. Primarily, the project covered the provinces of Agusan, Surigao and small portions of Davao and Misamis.
By the end of Phase I of the ILO/Finland project, it was clear that interest in manual harvesting technologies was limited and technology dissemination and transfer had been unsuccessful. There were numerous reasons for this lack of success. For example, by 1977, not a single study related to forest harvesting technology had been carried out by the Philippine Forest Research Institute (FORI). Most attention was directed at silvicultural problems and expertise was focused on natural forests. In addition, weak coordination between FORI and BFD often resulted in research that was considered impractical and irrelevant for field application. Moreover, it was commonly argued by senior staff of FORI and the University of the Philippines at Los Baños (UPLB) that new tools and more efficient harvesting techniques and methods might have a negative impact on the remaining dipterocarp forests. It was reasoned that the estimated 200,000 (in 1976) upland families practicing shifting cultivation might adopt these new technologies to cut more timber and expand their fields. The new tools, techniques and methods introduced by the ILO/Finland project were thus deemed to be inappropriate at that time by mainstream forestry organizations.
Interestingly, however, the results were taken up by several international organizations, among them FAO, which started to disseminate the findings from the first phase of the project in several other tropical countries. Based on their successes, a second phase of the project in the Philippines was then conducted between 1980-1982. An important lesson learned from the first phase was the need to manufacture the improved implements and tools for manual and animal-based harvesting locally.
Slowly, during the second phase, more Filipino foresters started to favor the idea of developing technologies appropriate for harvesting plantation-grown forests. At the same time, more ordinary people and non-governmental organizations (NGOs) supported expanded efforts to shift wood production away from the depleted natural forests by increasing plantation forests.
However, strong opposition still existed within the government itself, vis-à-vis the utilization of these plantations of fast-growing tree species. One major obstacle lay in the forestry legislation of the Philippines, which at that time strictly prohibited the use of manual and animal-based forest harvesting technologies, the use of circular sawmills, etc. Still, with the support of a few younger foresters in high positions in the BFD, by then renamed the Forest Management Bureau (FMB), the process of reformulating and amending the country's forestry legislation began in 1981. This gradual change in thinking and legislation paved the way for subsequent introduction and adoption of manual and animal-based harvesting technologies.
