The threshold point of Chromated Copper Arsenate (CCA) and Creosote Oil preservatives for the treatment of Gmelina arborea wood against subterranean termites was investigated. Wood samples from 15 years old Gmelina arborea trees were cold-dipped with CCA at 4%, 3% and 2% concentration levels while Creosote oil was used undiluted as well as at 1:1 and 1:3 Creosote oil - kerosene mixtures. The treated samples and control were exposed to termite attack at the timber grave yard, Federal University of Technology, Akure, Nigeria for 36 months. The result revealed the efficacy of CCA in the protection of Gmelina wood at the three concentration levels for the 36-month period with samples maintaining an ASTM mean visual rating of 10 (sound) at 2, 3 and 4% CCA treatment levels. Creosote Oil provided protection for only 12 months period as it recorded heavy attack and failure at the end of 30 months thereby suggesting a post-treatment schedule every 12 months for the undiluted Creosote oil in order to sustain protection of the wood. It could be concluded that 3% concentration level is the threshold value for CCA wood treatment while creosote oil could only be used undiluted for 12 months, its dilution with solvent reduced its potency.
PAPER TITLE :THRESHOLD DETERMINATION FOR CHROMATED COPPER ARSENATE AND CREOSOTE OIL FOR TERMITICIDAL TREATMENT OF
APPLIED TROPICAL AGRICULTURE | VOLUME 20 NUMBER 2 2015
- Author(s) : Owoyemi, J.M. and Olufemi, B.