“FORWOOD”

“FORWOOD”

The science of forest measurement in PNG (forest mensuration) was reflected in the development of forest assessment techniques for the location and estimation of current volumes of commercial timber resources in PNG, coupled with detailed mapping of landforms and species identification and distribution, in the period from the 1940’s to the 1970’s through the efforts of Australian foresters working in PNG’s forests.

During this thirty year period, foresters had to address war reconstruction, resource owners concerns, training of PNG’s foresters, botanical issues as identification, timber attributes of various species, mapping, development of a viable timber industry, metrication, currency changes, self government issues, computerisation, digitisation, photogrammetry and development of timber markets for many unknown species. As described in PNGAF Magazine Issue # 9B-5A OF 8th June 2021 p 45, from the Department of Forests publication New Horizons4 p 8 in 1972, PNG forests are divided into seven fairly homogeneous systems.

Forest System Specified Timber Area Area in thousands of hectares Volume in thousands of cubic metres (M3) Volume in thousands of cubic metres (M3)

0.5 – 1.5 metres GAB*

1.5 metres + GAB* Western Papuan Not available 3000 (est) Not available Not available Papuan South Coast Abau 90 3540 4365

South East Coastal Aroa 45 1179 1179 Sagarai Gadaisu 48 4250 3303

Musa 80 4719 2478 Kumusi 28 2360 2360 Ioma 182 11780 10380 Mai’ama 24 2830 2950 Bismarck Open Bay 104 4480 7080 Ania Kapiura 110 7080 5660 Kandrian 121 7790 8260 Arowe 157 8260 8730 Kapaluk 103 6135 6135 Melkoi 27 2360 1650 Nakanai n/a 2360 4955 Kaut 10 470 470 Solomons Torakina 13 945 1160 Sepik Ramu Vanimo 239 8495 10620 Middle Ramu 131 5665 5665 Highlands Giluwe n/a Not available 1840 Jimi n/a Not available 5190

TOTAL * Girth above buttress. 1,512 81,600 83,000

4 “New Horizons – Forestry in Papua New Guinea a Dept of Forests Publication 1973 Jacaranda Press. 5

The above table details an appreciation of the work performed by Australian foresters to establish the first PNG national forest inventory i.e., the standing assessed commercial forest resource by major forest types. The Department of Forests reported that the forest resources were extensive and varied in composition. Some 200 species had economic potential but only some 30 species accounted for the bulk of merchantable timber. By 1972, approximately onethird or 4.4 million hectares had been classed as having economic potential and assessed to a level where development planning was possible.

Forest Systems 5 Dept of Forests PNG 1970.

In 1946 some 14,518,219 hectares had been investigated (figures reviewed in 1957) of which 5273240 hectares were under 10 degree slope and the area of potential forest type was estimated to be some 274731 hectares.

The national forest inventory in PNG was largely completed by 1968 describing standing log volume and areas for specified timber areas. This was described in New Horizons 19726p7. Of the PNG total land mass of 46,886,000 hectares, tree cover was some 40,000,000 hectares of which commercially accessible forest was some 13,000,000 hectares.

By 1975 some 4,800,000 ha had been covered. By the late 1980’s, over 7,400,000 hectares had been covered.

After the mid 1960’s, - foresters had the advantages of developments in transportation such as helicopters.

In the late 1960’s and early 1970’s data processing moved from mechanical calculators to the advent of then primative elctronic computers.

By 1975, foresters had established the location and commercial volumes of timber resources by various botanical forest types throughout PNG. They had developed global techniques for the assessment of commercial sawlog and pulpwood volumes together with volume table compilation for the mixed rainforest species. They had identified botanical and timber characteristics for the various species .

This magazine (PNGAF Magazine Issue 9B-5B) describes the forest mensuration criteria under which the Department of Forests undertook the national forest inventory. It was a team effort because as previously described, it required correct mapping (refer PNGAF MAG ISSUE # 8 of 1 February 2021 – Department of Forests Mapping Section), correct botanical

5 Dept of Forests PNG 1970 Forest Systems of Territory of Papua and New Guinea. 6 New Horizons – Forestry in Papua New Guinea a Dept of Forests Publication 1973 Jacaranda Press. 6

attributes (refer PNGAF MAF ISSUE # 6 of 8th February 2021- Lae Botany) and timber attributes (forthcoming PNGAF MAG ISSUE).

It was after 1975, that advances in photogrammetry occurred with the introduction of satelllite coverage of forested areas. This enabled a much more rapid appreciation of forest cover although detailed species and volume aspects still required much ground work.

In recent times since 1975, although PNG was and is still interested in the commercial volumes of standing timber, the demand for more and better information from forests has prompted the development and application of new instrumentation in addition to persisting with continued on-ground measurement.

These advances allow PNG to undertake:

• Growth and yield/productivity studies in natural and planted forests. • Measuring the effects of silvicultural management practices on stem form, wood quality, tree growth and stand development. • Development of total and merchantable volume equations for estimating the biological asset value of tree stands, and biomass tables for carbon estimation. • Development of non-destructive sampling methods for volume, biomass, and wood quality estimation. • Studying the impacts of long-term environmental changes to the growth of trees and productivity of forests. • Advanced scientific methods for measuring and monitoring the impact of environmental conditions such as climate change on forest productivity, structure, and diversity.