The paper is the result of five years field study of wood degradation patterns in three ecological forest zones (Guinea Savannah, Tropical rain forest and mangrove forest zones, respectively). It involved 800 residential buildings and 700 electric overhead transmission poles. The methodology used was a modified Eslyn (6) test. A high rate of Ascomycetes and Basidiomycetes attack especially on the windward side of residential buildings was noted. A high incidence of subterranean termite attack as well as their ability to bridge resistant structures to reach their ultimate host was recorded. Powderpost beetles attack in household furniture and fittings made of non-durable wood and sapwood were common, but particle board proved immune. Overhead electric transmission poles pressure treated with cole tar based preservatives proved very resistant to biodeterioration. Seasoning defects are a common feature on the windward side of buildings and a major problem in poles. The author concluded that because of the favourable climate, pressure or other deep penetration treatments is desirable for all non-durable woods in tropical climates. Wood preservative formulations for utility poles should possess some dimensional stabilization properties. Remedial treatments were also recommended for dry rot, termite and powderpost beetles in existing structures.

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