Anti-Termite Efficacy of Selected Leaf Extracts on Pycnanthus Angolensis Wood: A Comparative Study

Wood is widely used in construction and manufacturing but is highly prone to biodeterioration, particularly in humid tropical regions. Conventional preservatives such as chromated copper arsenate (CCA) are effective but pose environmental and health risks, creating interest in more sustainable and less hazardous alternatives. This study assessed the preservative performance of leaf extracts from Azadirachta indica (neem), Chromolaena odorata (Siam weed), and Cedrela odorata (Spanish cedar) on Pycnanthus angolensis, a non-durable Ghanaian hardwood. Extracts were prepared with ethanol and water at 5%, 10%, and 20% w/v concentrations, and untreated samples served as controls. An in-ground field test was conducted, and termite resistance was evaluated by percentage weight loss. Untreated samples recorded the highest weight loss (93%), confirming the high susceptibility of the wood. All extract treatments reduced degradation to varying degrees. Neem performed best, with an average weight loss of 79%, followed by Chromolaena odorata (85%) and Cedrela odorata (88%). Ethanol extracts were more effective than water extracts, particularly at higher concentrations, with the most notable relative reductions observed at 20%. ANOVA confirmed significant effects of leaf type, solvent, and concentration. Although the treatments resulted in only partial protection and substantial biodeterioration remained, the findings demonstrate relative improvements compared to untreated wood. Neem leaf extracts, particularly ethanol-based treatments at 20%, showed the strongest comparative performance under the conditions tested. However, the results are based on a 90-day, short-term, single-site field trial and do not assess toxicity, leachability, or long-term environmental behavior.