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Poplar and preservative treatment – a literature review
By Dean Satchell, October 2026.
Download Literature_review_poplar_preservative_treatment_Oct-2026 (pdf)
Executive summary
Research is required on distribution patterns of water-based preservative in poplar. This report provides a review of the literature and recommendations on best treatment practice.
Best practice will require:
- Kiln dried timber
- Extending pressure period to refusal (2-3 hours).
- A Bethell full cell process, with at least 30 minutes vacuum (100 kPa) applied before fluids are added to the vessel, followed by flooding while maintaining a vacuum of -80 kPa or better. Then pressure of 1400 kPa, held for 2-3 hours (until refusal), then drained before applying vacuum of -85 kPa or better, held for minimum 20 minutes
- For research into penetration and distribution variables, use water with a dye-containing aqueous solution (0.05% rhodamine B).
- For deployment, a treatment charge could use CCA treatment in the first instance, potentially followed by ACQ and micronised copper to compare distribution patterns between these water-based preservatives.
Following successful preservative distribution and development of an appropriate schedule, durability testing will be required to assign a hazard classification according to retention levels. This step is critically important.
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