Eucalyptus camaldulensis poles were treated with 50 : 50 creosote-light
diesel oil mixture. The poles contained an average of 53.85% sapwood which
was readily perishable by wood destroying organisms if untreated. The poles
were treated by the Bethel Full-Cell process using varying pressure and
duration to evaluate the effect on penetration and retention of the preservative
mixture. It was found that with the simultaneous increase of both treating
pressure and time, no significant increase in pentration was achieved. On the
other hand, with the increase of treating pressure only, the retention of
pressrvative in the sapwood was increased significantly. A penetration of 3.5
cm with retention of 318. 45 kg/m3 in the treated sapwood could be obtained
by using 10.57 kg/cm2 pressure for 3 hours. This amount of penetration is
considered adequate to protect the sapwood region of the pole.