Incising to improve penetration and retention of Copper Chrome Arsenate (CCA) in the butt end of Eucalyptus saligna telegraph poles was investigated. Debarked, seasoned (15% MC) butt-end samples from full size telegraph poles were incised using four patterns of incisions, sealed at the top or small diameter end, and pressure treated, together with un-incised samples, with CCA-C (3.0% oxide type) at a commercial pole treatment plant, using a full cell process. After conditioning under cover for 6 weeks to allow fixation and air-drying to 15% MC, samples were leached in running tap water for 12 days, re-dried to 15% MC, retentions calculated on a weight gain basis and compared. Discs were removed from the middle 50mm sections of samples, sprayed with Chrome-azurol S, and average radial penetration computed. In comparison to un-incised samples, both penetration and retention were substantially improved in samples with closer incisions of 20 mm x 20 mm, by 59.9 %, or 79.3 mm and 59.0%, or 28.3 Kg/m3 respectively. For the wider incisions of 40 mm x 40 mm, improvements were lower, 13.1%, or 56.1 mm for penetration and 19.7%, or 21.3 Kg/m3 for retention. Un-incised samples achieved consistently lower average penetrations of 49.6 mm and retentions of 17.8 Kg/M3. Butt-end incising maybe a feasible technique for improving the otherwise unacceptable short service lives of eucalyptus telegraph poles in the country. Intensity, depth, and method of incising, together with appropriate treatment schedules, need to be investigated further.

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