Macro propagation of dipterocarps

LOS BAÑOS, Laguna — Fourteen Philippine dipterocarp species have been successfully propagated in a scientific breakthrough achieved by a Department of Environment and Natural Resources (DENR) bureau based here.

The research headway was chalked up by Forester Mitzi T. Pollisco of the Ecosystems Research and Development Bureau (ERDB).

Her research, titled "Macro-propagation of dipterocarps through seedlings, wildlings and rooted cuttings," was monitored by the Los Baños-based Department of Science and Technology-Philippine Council for Agriculture, Forestry and Natural Resources Research and Development (DOST-PCARRD).

In her project, Pollisco developed a method to increase the percentage survival of wildlings in the country through the use of the wildling recovery chamber, raise different dipterocarp species in the hedge garden and produce the limited planting stocks using the non-mist propagation system.

In the system, which Pollisco developed to meet the demands for large-scale nationwide planting requirements of dipterocarps, some cuttings were treated with rooting hormones, others without. The purpose was to determine which species would root even without the aid of these hormones.

To induce rooting and shoot production, cuttings were then placed in the non-mist propagation chamber for two to three months.

After a month, these were transferred to the nursery for hardening purposes.

Initially, Pollisco found that not all dipterocarp species were difficult to root. Some species rested even without the aid of rooting hormones provided they are juvenile.

More important, dipterocarp species are amenable to vegetative propagation by cuttings using the non-mist propagation system.

To date, the DENR-ERDB researcher has successfully propagated white lauan, red lauan, guijo, tanguile, apitong, bagtikan, yakal-saplungan, dagang, palosapis, panau, dalingdingan, gisok-gisok, almon and hagakhak.

Dipterocarps belong to a group of forest trees known for their large timber and superior wood quality, wrote PCARRD’s Clarinda Apolinar and Butch Pagcaliwagan.

"They play an important role in climatic regulation, contribute largely to environmental stability and stand as a vital component of watersheds in the country," they said.

Over the past 20 years, PCARRD noted, the country lost about 8.75 million hectares of dipterocarp forests. Such great loss has been attributed to excessive logging and slash-and-burn (kaingin) agriculture in the uplands.

During the 1977-1997 period, the country’s dipterocarp forests shrank considerably.

Other reports state that it was during the decades of the 1960s and 1970s that logging and clearing f forests through kaingin farming in the country peaked, with more than 300,000 hectares cleared every year.

Deforestation went down to an average of 200,000 hectares a year in the 1980s and further down to about 130,000 hectares a year in the 1990s and today.

At the early period of the Spanish colonization of the country, forests covered about 27.5 million hectares or 92 percent of the country’s total land area of 30 million hectares.

By 1920, there were still 18.7 million hectares of natural forests. This shrank to 17 million in the mid-1930s.

What remained as of 1997 were only 5.4 million hectares, a big chunk of which were non productive. Today, there are only about 700,000 hectares of virgin forests which the rest consist of mossy and second growth forests.