Effect of Chemical Presevatives on Service Life of Selected Wood Species Treated against Pests and Diseases

The effect of different chemical preservatives on the service life of selected wood species was evaluated in a field plot at the Forestry research site, University of Uyo, Akwa Ibom, Nigeria. Three wood species, Triplochiton scleroxylon K. Schum (Obeche), Gmelina arborea Linn (Gmelina), and Terminalia ivorensis A Chew (Idigbo-Black afara), were used for this study. Two chemical preservatives namely: acid copper chromate and copper citrate at concentrations of 0%, 0.37%, 0.75%, and 1.5% each and a mixture of the two preservatives (mixed preservative) at the given concentrations were used in treating stakes of these wood species, and their retentions were determined. Service life of the stakes was evaluated at the end of six months; and insect, pest and fungi that infected them were identified. The result indicated that obeche had the highest mean retention of 4.04 kg/m super( 3). The result also showed that the retention increased with increase preservative concentration, the highest retention of 6.80 kg/m super( 3) was obtained with mixed preservative at 1.5% concentration.