The long-term performance of carbon-based preservatives may be limited by detoxification by microorganisms. This study identified primary colonizers of wood treated with carbon-based preservatives that may contribute to detoxification of carbon-based biocides. Wood coupons treated with three different carbon-based preservatives were subjected to a repeated wetting and drying cycle in an accelerated field simulator for 2, 4, 8, 16 and 32 weeks. After exposure, samples were analysed for triazoles or DDAC concentration and microorganisms were isolated and identified using culturing onto malt extract and Luria Bertani media followed by DNA extraction and sequencing of representative isolates. Bacteria from the genus Pseudomonas were found on all three treatments at all sampling times. Few fungal isolates were obtained; one isolate was identified as a Trichoderma sp., while the remainder were identified as a Penicillium species. The data indicated a possible succession in species that may be caused by the change in amount of active preservative remaining in the samples over the duration of the experiment. No difference was observed in bacterial colonization based on the preservative used in the experiment. Future work should focus on determining the role of Pseudomonas in preservative detoxification, and finding preservative formulations capable of inhibiting colonization by Pseudomonas.