Chapter 2: Forest Resource Assessment

The timber resource assessment is designed using stratified samplings points spread across the FMU in areas approved by the Forest Authority.  As logging progresses, the present data will be updated accordingly.  The output of Annual Allowable Cut (AAC) is the analysis of timber resources in natural forests in the FMU.  Timber resource assessment was done with the following objectives:-

  • Estimate the mean and total growing stocks by species group;
  • Achieve a precision of estimates within 20% sampling error at 95% probability level.

Forest Resources and Forest Research

  • More than 20 PSPs were established within the FMU area.  The objective for the establishment of PSP is to determine the Annual Allowable Cut (AAC) to sustainably manage this FMU area.  
  • The calculation of AAC was based on the PSP result for growth simulation.
  • A repeated simulation runs have been carried out using different harvesting scenarios and their results were analyzed in terms of sustainability with estimated harvested volume that will be achieved.
  • It has a 25-year cutting cycle with an extractable of 9 to 19 trees per Ha and an average harvestable volume of 42.2 m3/ha.
  • This calculation serves as a temporary indication of sustainable harvestable volume.
  • Identification and monitoring of Endangered, Rare and Threatened (ERT) Species and their habitats and dynamism in sustainably well managed forest area.
  • Non-Timber Forest Product (NTFP) like palm, bamboo, rattan, wild fruits and edible wild vegetable are present in the FMU.
  • Timber stock as recorded from the forest research (30 cm dbh and above) is averaged at 59 trees or 65.55 m3/ha, 30cm – 49.9cm is averaged at 43 trees or 31.63 m3/ha and 50cm and above is averaged at 16 trees or 33.92 m3/ha.
  • FMU has the total of 17 ERT species of fauna with 14 species consisting of mammals, 2 reptiles and 1 insect.
  • Rate of Annual Harvest:
  • The average of harvestable yields within the research PSP is 42.2 m3/ha, derived from high density and low density of productivity areas based on fair representation of PSPs.
  • The preliminary growth calculation of MAI is 0.4cm per year and 1.69 m3/ha/year.  The basal area is calculated as 27.05 m2/ha.
  • Allowable Cutting Area (ACA) is 2,204.5 ha.
  • AAC is 75,725 m3 of production limit for the initial planning of this FMP.

Forest Zoning

  • Production area – Mixed Hill Dipterocarp Forests for the production of mainly timber.
  • Conservation area – undisturbed and partially disturbed which would serve as reference as continuous in research studies, refuge and breeding sites, as well as timber tree seed production and conservation of genetic diversity.
  • International Boundary Buffer Zone
  • Inundated Area (Areas affected by the proposed Baleh Hydro-Electric Project)

Types of Zones and Sizes in Hectares:

Area Type of Zones Area (Ha) Percentage (%)
      FMU Area Production Forests 47,626 74.5%
Terrain IV 2,237 3.5%
Buffer Zones 326 0.5%
Kerangas 393 0.6%
HCVF 700 1.1%
International Boundary Buffer Zones 3,830 6%
Sub-total 55,112 86.2%
Area excluded from FMU Areas Affected by Baleh HEP 2,091 3.3%
Conservation Area 5,290 8.3%
100 m HEP Buffer Zones 1,397 2.2%
Sub-total 8,778 13.8%
TOTAL Licensed Area 63,890 100%