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Marine test of synthetic pyrethroids at Sekondi, Ghana
1981 - IRG/WP 478
The trials reported here are part of a new series of marine exposure tests (Ghana Series 80) begun in October 1979 and designed to assess the natural durability if indigenous timber species and the performance of preservatives and preservative combinations in indigenous wood substrates in Ghana's coastal waters.
F F K Ampong


Natural Resistance of timbers to marine borer attack. COIPM/IRG CO-OPERATION. Final report concerning panels exposed in the sea at Sekondi, Ghana
1979 - IRG/WP 449
The test was carried out according to Document COIPM/72.044, Revised procedure for the testing of naturally durable timbers against marine borers. The panels of the three species remaining in the test at the end of 1978 were removed and assessed visually. An average rating was given to the panels of each species.
F F K Ampong


IRG/COIPM INTERNATIONAL MARINE TEST - to determine the effect of timber substrate on the effectiveness of water-borne salt preservatives in sea-water. Progress Report 20: Report on the inspection of specimens at Sekondi, Ghana after 48 months
1985 - IRG/WP 4116
The results of the second inspection of CCA- and CCB-treated test panels exposed at Sekondi, Ghana, in June 1980, are presented. The panels of Pinus sylvestris treated with 3% CCA are stil unattacked after 48 months. Panels treated with 10% CCA and still in test (Fagus sylvatica, Pinus sylvestris and Alstonia scholaris) are still free of attack. Locol species treated with 3% CCB have all been destroyed. Of the panels treated with 10% CCB recovered from the bottom of the sea, those of Ongokea gore were shown by X-radiography to be in various stages of attack by teredinids. One recovered panel of Erythrophleum guineense and four of Mitragyna stipulosa remain free of attack. Teredinids constitute the major hazard.
F F K Ampong, N Asare-Nyadu


4th Report on condition of panels at Sekondi, Ghana
1978 - IRG/WP 445
F F K Ampong


Natural decay resistance of some lesser-used tropical hardwoods from Ghana
2002 - IRG/WP 02-10438
Ghana is a tropical African country that is rich in diverse timber species. In order to reduce over-exploitation of the popular timber species and increase the resource base for the wood industry, lesser-used or lesser-known timber species are being promoted locally and for export. To do this successfully, it is essential to determine the physical, mechanical and biological properties of these timber species in order to determine their commercial potential. Natural decay resistance (natural durability) lesser-used tropical hardwoods from Ghana to the wood decay basidiomycetes (Gloeophyllum trabeum, Coniophora puteana and Coriolus versicolor) were determined according to EN 113 (1980). Fagus sylvatica (beech) was used as a reference timber. Based on mean weight losses (%), the timber species were ranked in order of decay resistance to G. trabeum as: Albizia ferruginea Benth. > Petersianthus macrocarpus Macbride > Amphimas pterocarpoides Harms. > Celtis zenkeri Engl. > Albizia zygia Macbride > Anopyxis klaineana Pierre Eng. > Antrocaryon micraster A. Chev.> Celtis mildbraedii Eng; to C. puteana as: Albizia ferruginea > Amphimas pterocarpoides > Petersianthus macrocarpus > Albizia zygia > Anopyxis klaineana > Antrocaryon micraster > Celtis mildbraedii > Celtis zenkeri and to C. versicolor as: Albizia ferruginea > Anopyxis klaineana > Amphimas pterocarpoides > Albizia zygia > Petersianthus macrocarpus > Antrocaryon micraster > Celtis zenkeri > Celtis mildbraedii. Natural durability ratings for the timbers in accordance with EN 350-1 (1993), were: Albizia ferruginea 1 (very durable), Albizia zygia 3 (moderately durable), Amphimas pterocarpoides 3 (moderately durable), Anopyxis klaineana 3 (moderately durable), Petersianthus macrocarpus 4 (slightly durable), Celtis. mildbraedii 5 (not durable), Celtis zenkeri 5 (not durable), and Antrocaryon micraster 5 (not durable).
S A Amartey, F R Hanson


Observations on the effect of two preservatives on settlement and development of the marine wood-borer Martesia striata L
1983 - IRG/WP 498
Small heartwood specimens of three tropical hardwoods namely kusia or opepe (Nauclea diderrichii (De Wild) Merrill), emire or idigbo (Terminalia ivorensis A. Chev.) and subaha or abura (Mitragyna stipulose (D.C.) O. Kuntze) were treated with either creosote (BSS 144 type) or a copper-chrome-arsenic preservative and submerged in the sea at Tema, Ghana. They were regularly cleaned of fouling and observed for marine borer damage over a 36-month period. The evidence indicates: (i) the heartwood of each species resists Martesia striata L. infestation for nearly 24 months; (ii) creosote does not markedly inhibit initial settlement of Martesia striata (iii) once successfully established in creosote-treated specimens, Martesia striata develops in size at a much slower rate than those successfully settling on, and developing in, copper-chrome-arsenic treated wood samples of the same species; (iv) copper-chrome-arsenic (Tanalith CT 106) preservative inhibits the settlement of Martesia striata, but once settled the rate of growth of this borer differs little from that in untreated specimens.
J E Barnacle, F F K Ampong


Alternative timbers to Iroko (Milicia excelsa) for various end-uses: Ghana’s offer
2004 - IRG/WP 04-10518
There are hundreds of timber species indigenous to Ghana and several exotic species have been extensively planted. The timber industry in Ghana is very important to the country’s economy. Despite its small size relative to the world trade in timber products, it has the potential to be a driving force in the development of the Ghanaian economy. The industry is currently going through a period of change and restructuring which is largely brought about by the need to address the issues of a reducing resource and to use the available resource more efficiently and to greater economic benefit by promoting the lesser used species as alternatives to the over-exploited primary species and also by developing the tertiary processing sector. Iroko (Milicia excelsa) is one of the primary species currently facing extinction and Dahoma (Piptadanistrum africanus), Ekki (Lophira elata), Kusia (Nauclea diderrichii) and Papao (Afzelia bella) are lesser-used species being promoted as good alternatives to Iroko for various end uses. Properties (mechanical, biological) and volumes of these species are compared to those of Iroko.
S A Amartey, Zeen Huang, A Attah


IRG/COIPM INTERNATIONAL MARINE TEST - to determine the effect of timber substrate on the effectiveness of water-borne salt preservatives in sea-water. Progress Report 19: Report on the condition of specimens at Sekondi, Ghana after 42 months
1984 - IRG/WP 4109
The results of the first formal inspeation of CCA- and CCB- treated test panels exposed at Sekondi, Ghana, in June 1980, are presented. All untreated control panels of both reference and local species have been destroyed. Of the% CCA- treated specimens, only those of Pinus sylvestris (reference species) and Mitragyna stipulosa (local species) have not been attacked. 3% CCB-treated local species have been attacked. No 10% CCA- treated panels still in test have been attacked. The majority of CCB- treated panels (6% and 10% as well as 3% reference species) are missing.
F F K Ampong


IRG/COIPM INTERNATIONAL MARINE TEST - to determine the effect of timber substrate on the effectiveness of water-borne salt preservatives in sea-water. Progress Report 22: Report on the conditions of specimens at Sekondi, Ghana after 60 months
1986 - IRG/WP 4123
The results of the third inspection of CCA and CCB treated test panels exposed at Sekondi, Ghana in June 1980 are presented. None of the panels still in test, i.e. panels of Pinus sylvestris treated with CCA at 3 and 10%, Alstonia scholaris treated with CCA at 10%, Fagus sylvatica treated with CCA at 10%, and Erythrophleum ivorense and Mitragyna stipulosa both treated with CCB at 10%, shows any external evidence of borer attack. X-radiography, however, shows that only Fagus sylvatica panels treated with 10% CCA remain completely free of attack. The attacking borers are teredinids.
F F K Ampong, N Asare-Nyadu


The influence of extractives on the natural durability of selected Ghanaian hardwoods
2004 - IRG/WP 04-10530
A study of the durability of Nauclea diderrichii, Nesogordonia papaverifera, Corynanthe pachyceras and Glyphaea brevis in laboratory and field tests showed the first three species performed well against a range of fungi and termites. Sapwood of C. pachyceras also performed well against these biodeteriogens. The role of extractives in conferring natural durability was assessed. Total extractive contents of outer and inner heartwood of these species are presented, together with that of sapwood from C. pachyceras. Total extractive content was correlated against weight loss following exposure to C. versicolor. As extractive content increased then so did the durabilities of these species with the best correlation observed with C. pachyceras (R2 value = 0.67). Sequential extraction of these species using a range of increasingly polar solvents showed more polar solvents (particularly methanol and water) removed a greater proportion of extractives. These fractions normally had the greatest influence on natural durability when extracted blocks were exposed to C. versicolor.
C Antwi-Boasiako, A J Pitman, J Barnett


Decay resistance of coconut and rubber woods. Alternative wood species from Ghana
2006 - IRG/WP 06-10596
With the expanding local and world wide demand for tropical timbers, there is increased interest in the suitability of lesser–used timber species as alternatives for the forest based industries in order to ensure sustainable forest management. In the forests of Ghana, there are quite a number of timber species that are lesser known and have not been adequately used due to the absence of information on their properties. Two such lesser-used wood species are rubber wood (Hevea brasiliensis) and coconut wood (Cocos nucifera). We have determined the resistance of a treated and untreated coconut wood and rubber wood against selected brown and white rot decay fungi using the mini block method. Norway spruce and beech wood specimens were used as controls. After eight weeks of decay, mass losses were determined gravimetrically. The results showed that although both coconut wood and rubber wood were very resistant to all the decay fungi tested their resistance against the brown rot fungi were higher than the white rot fungi. Treatment of both wood species with a boron-based preservative increased their resistance considerably against all the decay fungi. The resistance of the treated coconut wood increased by 9% and 87% when exposed to S. lacrymans and T. versicolor respectively and that of the treated rubber wood increased by 43% and 82% when exposed to G. trabeum and H. fragiforme respectively. We however recommend that the treated woods should only be used where the risk of repeated wetting is very low in order to prevent leaching of the boron from the wood.
S Amartey, M Humar, B Donkor, F Pohleven