Copal (FAO, NWFP 6)

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4 HARD RESINS
COPAL


DESCRIPTION AND USES

The term copal applies to a large group of resins characterized by their hardness and relatively high melting point. They are soluble in alcohol. Up until the 1940s, or thereabouts, they were among the best of the natural resins for use in varnish and paint manufacture, and traded in very large volumes. In the oil-soluble form they were also used in the manufacture of linoleum. Copal has been produced from a large number of different tree species from many parts of the world - Africa, Asia and South America. Today, most copal of commerce originates from Agathis species of Southeast Asia: the Malay and Indonesian archipelagos in particular and, to a lesser extent, the Philippines.

Today, the major use of copal is as a varnish for wood and paper. It still finds use in road-marking paints, where the capacity of the resin to prevent bleed-through of road-making materials is beneficial, and there are numerous other, minor uses.

Until the decline in demand for copals brought about by the use of synthetic resins for varnish and paint manufacture, much of the copal was collected in the fossilized or semi-fossilized form. Nowadays, most of it is collected by tapping the living tree. Furthermore, many of the trees which are now tapped have been planted, and there is no longer dependence on the wild forest.

Historical introduction

Historically, the copals have been classified according to their geographical origin:

  • Congo copal. In the 1920s, 1930s and 1940s, the quantity of copal produced from the former Belgian Congo (now Zaire) far exceeded that from any other region of the world. From 20 tonnes in 1900, production rose to 12 000 tonnes in 1923 and 23 000 tonnes in 1936. The resin was all of the fossilized type, having fallen to the ground from the tree where it was produced as a result of natural exudation or from accidental injury. In many cases, the trees were no longer standing and the resin was recovered from below the surface of the earth, where it was located by exploratory prodding with a stick. The very hard, acidic materials were traditionally converted into oil-soluble forms for use in varnishes by a process known as "running" (subjecting them to high temperature heat treatment).
  • West African copals. These were collected and exported in moderate amounts before Congo copal became so important. Again, most of the resin was fossilized, and the copals were known in the trade by their country or place of origin, e.g., Sierra Leone, Cameroon, Angola and Accra copals.
  • East African copal. This was produced mainly in Tanzania and Kenya and was collected either in semi-fossilized form (from the soil below the tree where it fell), fossilized form (from the soil where the tree no longer existed), or by tapping the living tree.
  • South American copals. Brazilian copal is the best known and is still produced to a very small extent today, where it is known as jutaicica. It is usually collected as a semi-fossilized resin.
  • East Indian and Manila copal. These were copals produced from what is now Indonesia and nearby islands, and the Philippines. The term Manila copal arose from the time when Manila was the main port of export. Total production from this region in some years during the early part of the century reached 15 000 tonnes; then, the copal was collected both in the semi-fossilized form and by tapping. Today, this is the most important copal-producing region of the world and all of it is produced by tapping.

Apart from brief reference to the botanical sources of the African and South American copals (Plant Sources), the rest of the discussion below is confined to those copals which are still produced today: copal of mainly Indonesian origin and Manila copal ("almaciga"). Both are produced from Agathis species.

WORLD SUPPLY AND DEMAND TRENDS

Markets

Exports of copal from Indonesia and the Philippines for the period 1988-93, and their destinations, are given in Tables 17 and 18, respectively.

Total exports from Indonesia and the Philippines averaged about 2 300 tonnes annually during 1988-93. Most Indonesian copal (and some Filipino) is shipped via Singapore but Germany, which also imports directly from Indonesia, is a major onward destination and the most important in Europe. India and Japan import modest quantities directly from Indonesia. China (Taiwan) is the biggest importer of copal from the Philippines.

Imports of copal and damar into Japan during 1985-87 are shown in Table 19, although it is not possible to separate the two commodities. After 1987, copal and damar are not separated from "Natural gums, resins, gum-resins and balsams, n.e.s.". Combined imports of copal and damar averaged just over 400 tonnes/year in 1985-87.

Photo N.5 : Cleaning and sorting copal, Java, Indonesia. (Photo: J.J.W. Coppen)

Supply sources

Indonesia is by far the biggest producer and exporter of copal. After the fall in exports in 1989 from almost 2 500 tonnes the previous year (Table 17), levels have been remarkably constant at about 1 850 tonnes/year.

The Philippines is the second biggest producer of copal; exports during 1988?93 averaged about 350 tonnes/year with no clear trend.

In 1982, Sarawak exported just over 50 tonnes of copal; Malaysian exports since then record only very small quantities of copal.

Papua New Guinea has been a small producer and exporter in the past but the present scale of production from this source (if any), and other islands of the Pacific, is not known.

Quality and prices

The quality of copal which is collected is very variable, depending inherently on the species from which it is obtained (which may affect its solubility properties) and the manner in which it is collected: whether by tapping or by picking from the ground in a fossilized form. After cleaning (removing pieces of bark and other foreign matter), different grades of copal in trade are distinguished by their hardness, colour and size of the pieces, as well as the state of cleanliness. Pale, clean pieces, with good solubility in alcohol, are the best quality.

Present (mid-1995), indicative prices for some Indonesian copal grades shipped from Singapore (CIF London) are:


"Clean scraped chips" US$ 1 500/tonne

"Medium scraped chips" US$ 1 000/tonne

"Small chips" US$ 900/tonne

Prices have been fairly stable in recent years.


PLANT SOURCES

Botanical names (present day Asia/Pacific copals)

Family Araucariaceae: Agathis spp.

The taxonomy of Agathis has been, and still is, confused and in the past, numerous different species names have been cited as the source of copal; the most common one has been A. alba. In some cases, even now, plantation trees, grown and tapped in Indonesia, are referred to simply as "Agathis spp.", with no attempt to give a full name.

WHITMORE (1977, 1980) and de LAUBENFELS (1989) recognize more than a dozen species of Agathis - which extend from peninsular Malaysia, across the Malay and Indonesian archipelagos to islands in the Pacific (as far east as Fiji), and south to the coastal regions of Queensland, Australia, and New Zealand - although the authors differ on some points. They agree that the natural stands on Peninsular Malaysia, Sumatra and Borneo which are sources of copal are those which should be designated A. borneensis Warb., but trees in the Philippines and Sulawesi are considered to be A. dammara (Lamb.) Richard by Whitmore and A. philippinensis Warb./A. celebica (Koord.) Warb. by de Laubenfels. Other copal producers include A. labillardieri Warb.

The identity of the extensive plantation Agathis which are tapped on Java is not known (to the present author) and to avoid confusion no species name is attached to Agathis hereafter in this discussion.

Historical copals

(N.B. The genera given below all belong to the family Leguminosae. However, the species listed are those attributed by HOWES (1949); their current acceptance in terms of botanical nomenclature is not known and some of the names may be obsolete.)

Congo copal

Mainly or entirely from Copaifera demeusei.

West African copals

Copaifera copallifera, C. demeusei, C. mopane.

East African copal

Almost entirely from Trachylobium verrucosum.

South American copals

Various Hymenaea spp., especially H. courbaril L.

Description and distribution (Asia/Pacific copals)

Agathis is the most tropical of all conifers. The copal-yielding species are very tall trees, up to 60 m high, often with a near-cylindrical bole. However, there can be some variation in the characters of the living tree, as well as the ecological conditions under which it occurs. It is grown widely as a timber tree on Java (over 100 000 ha) and other parts of Indonesia.

The distribution of Agathis has been discussed above.

COLLECTION/PRIMARY PROCESSING

Nowadays, most copal, at least that intended for international markets, is obtained by tapping the tree, rather than collecting fossilized resin from the ground. In the tree, the resin resides in the living inner bark of the trunk and tapping involves making incisions into the bark and collecting the exudate. Fresh cuts are made at suitable intervals - a few days or a week or more - gradually moving up the tree. The size and shape of the cuts, the extent to which they might penetrate the wood, and their frequency of application have changed over the years and still vary according to the country or region in which tapping is undertaken, or the traditions of the communities involved.

Present practice on Java is for the tapper to return to the tree to make fresh incisions every 3?4 days; up to four or more small tin cups may be in place at different points on the tree at any one time, depending on the size of the tree. In the Philippines, research has been undertaken using tapping methods very similar to those used in tapping pine trees (involving use of sulphuric acid as a chemical stimulant), but it is not known whether such methods are used commercially.

Collected resin is cleaned by sieving and hand picking to remove foreign matter, and packed in sacks for transfer to points of sale, either nationally or internationally.

Yields

Resin yields are very variable and depend on a large number of factors: genetic, environmental and practical (i.e., method of tapping used). Annual yields of 16-20 kg have been reported from good trees in the Philippines and Papua New Guinea, while average yields have been variously estimated at 2 kg or as much as 10-12 kg. Recent tapping trials at three sites in the Philippines resulted in average annual yields of 1.2 kg, 3.7 kg and 5.6 kg/tree.

Recent research in Indonesia and the Philippines has shown that thick-barked Agathis yields significantly more resin than thin-barked trees (in one study in Indonesia, almost nine times as much), and that tapping in the morning and at the side of the tree which maximizes the length of time that sunlight falls on it is beneficial to resin yields.

VALUE-ADDED PROCESSING

No further processing is carried out until the copal is formulated for use by the end-user; this may involve heat treatment, dissolution in a suitable solvent and/or chemical processing. The latter may be carried out by a specialist chemical processor and usually involves preparation of copal esters to neutralize the natural acidity of copal and render it oil-soluble.

PRODUCTS OTHER THAN RESIN

Agathis produces a high class, much valued, utility timber and it is grown widely as a timber tree. In Malaysia, it is the most important commercial softwood, and it is also widely planted in Indonesia.

DEVELOPMENTAL POTENTIAL

Resin-yielding Agathis are planted for timber, rather than as a source of resin, and tapping of plantation trees is therefore a secondary activity to that of timber production. The proportion of planted trees which are tapped commercially is not known, but it is probable that it is a relatively small proportion and that copal production from such sources could be increased significantly if demand and the economics of production were favourable.

By nature, the trees are very large and there is little scope for agroforestry-type interventions. However, taking into account the fact that there is a steady demand for copal, that some copal will continue to be obtained from wild sources, and that importers are always prepared to consider new, reliable sources of supply, there may be some opportunities for new producers - perhaps for some of the Pacific islands where cooperatives can be organized.

SELECTED BIBLIOGRAPHY

  • ANON. (1962) Almaciga Resin. FPRI Technical Note No. 35. 4pp. Laguna, the Philippines: Forest Products Research and Industries Development Commission.
  • BILLING, H.J. (1944) Congo Copal. The Oil and Colour Trades Journal, 3(Nov), 666-668.
  • BOWEN, M.R. & WHITMORE, T.C. (1980) The tropical conifer Agathis as a potential plantation tree. Paper presented at IUFRO Symposium and Workshop on Genetic Improvement and Productivity of Fast-growing Tree Species, Sao Paulo, Brazil, August 1980.
  • BOWEN, M.R. & WHITMORE, T.C. (1980) A Second Look at Agathis. Occasional Paper No. 13. 19 pp. Oxford: Commonwealth [now Oxford] Forestry Institute, University of Oxford.
  • CONELLY, W.T. (1985) Copal and rattan collecting in the Philippines. Economic Botany, 39(1), 39-46.

GONZALES, E.V. and ABEJO, F.G. (1978) Properties of Manila copal (almaciga) resin from 15 different localities in the Philippines. Forpride Digest, 7(1), 68-69.

  • GONZALES, L.L., CRUZ, V.C. & URIARTE, M.T. (1986) Effects of seasonal variation and sulphuric acid treatment on the resin yield of almaciga (Manila copal). Sylvatrop, 11(1-2), 43-54.
  • HALOS, S.C. (1983) Factors affecting quality and quantity of almaciga resin. National Research Council of the Philippines Research Bulletin, 38(1), 70-113.
  • HARRISON-SMITH (1941) Kauri gum. New Zealand Journal of Forestry, 4, 284-292.
  • HOWES, F.N. (1949) The copals. pp 93-103. In Vegetable Gums and Resins. 188 pp. Waltham, USA: Chronica Botanica.
  • De LAUBENFELS, D.J. (1989) Agathis. pp 429-442. In Flora Malesiana, Series I, Vol. 10. Dordrecht, The Netherlands: Kluwer Academic Publishers.
  • ORDINARIO, F.F. & TONGACAN, A.L. (1979) The influence of diameter and sulphuric acid on the resin yield of almaciga (Agathis philippinensis Warb.). Forpride Digest, 8(2), 21-34.
  • RIYANTO, T.W. (1980) [Small notes on copal resin] (in Indonesian). Duta Rimba, 6(42), 23-28.
  • SAULEI, S.M. & ARUGA, J.A. (1994) The status and prospects of non-timber forest products development in Papua New Guinea. Commonwealth Forestry Review, 73(2), 97-105.
  • SOENARNO, M.M.I. (1987) Copal production on Agathis spp of varying bark thicknesses, West Java. Duta Rimba, 13(Mar/Apr), 3-6.
  • SOENARNO, M.M.I. & BASARI, Z. (1984) [Study on the improvement of copal tapping procedure at Sukabumi Forest District, Java, Indonesia] (in Indonesian). Jurnal Penelitian Hasil Hutan, 1(3), 34-38.
  • SUMANTRI, I. (1991) [Relation between tree diameter and copal production during tapping of Agathis spp] (in Indonesian). Duta Rimba, 17(135-136), 42-45.
  • SUMANTRI, I. & DULSALAM (1991) [Manipulation of tapping design to increase resin yield of Agathis] (in Indonesian). Jurnal Penelitian Hasil Hutan, 9(1), 1-4.
  • SUMANTRI, I. & SASTRODIMEDJO, S. (1976) [Tapping Trials of Agathis Hamii M. Dr. in South Sulawesi] (in Indonesian, English summary). Report No. 58. Bogor, Indonesia: Forest Products Research Institute.
  • TONGACAN, A.L. & ORDINARIO, F.F. (1974) Tapping of almaciga resin. The Philippine Lumberman, 20(12), 18-19, 22-23, 25.
  • WHITMORE, T.C. (1977) A First Look at Agathis. Tropical Forestry Paper No. 11. 54pp. Oxford: Commonwealth [now Oxford] Forestry Institute, University of Oxford.
  • WHITMORE, T.C. (1980) Utilization, potential and conservation of Agathis, a genus of tropical Asian conifers. Economic Botany, 34(1), 1-12.
  • WHITMORE, T.C. (1980) A monograph of Agathis. Plant Systematics and Evolution, 135, 41-69.

Table 17. Copal: exports from Indonesia, and destinations, 1988-93 (tonnes)

. 1988 1989 1990 1991 1992 1993 Total 2485 1811 1766 1880 1863 1886 Of which to : Singapore 1807 1233 1130 1173 1332 1362 Germany 262 405 435 495 390 258 India 38 45 90 105 15 57 Japan 38 60 38 63 25 25 Hong Kong 22 51 30 14 30 83 China (Taiwan) 270 - 15 - - - Pakistan - - 28 30 71 87 UK 45 - - - - - Netherlands - 17 - - - - France - - - - - 14

Source: National statistics


Table 18. Manila copal: exports from the Philippines, and destinations, 1988-93 (tonnes)

. 1988 1989 1990 1991 1992 1993 Total 407 345 288 363 272 382 Of which to : China (Taiwan) 184 196 139 224 171 286 Hong Kong 91 72 78 84 60 52 Singapore 70 57 60 44 30 - USA 56 20 - 5 - 14 France 6 - 11 6 - - Germany - - - - 11 30

Source: National statistics


Table 19. Copal and damar: imports into Japan, and sources, 1985-87 (tonnes) . 1985 1986 1987 Total 441 441 347 Of which to : Indonesia 426 414 347 Singapore 15 27 15 Malaysia - - 30

Source: National statistics