Treatability study of four under-utilised species of Malaysian hardwoods using the pressure treatment method.
Four under-utilized Malaysian hardwoods, Lithocarpus spp., Pouteria malaccensis, Irvingia malayana, Parkia speciosa, and two popular timber species, Dyera costulata and Intsia palembanica, were studied. All the seasoned specimens were vacuum-pressure treated with 3% CCA solution. The moisture content and density of all the selected timbers were determined prior to the treatment. Net dry salt retention after treatment was measured using the atomic absorption spectrophotometer. All the species except I. palembanica attained the minimum net dry salt retention of 5.6 kg/m3 as specified by the Malaysian Standard MS 3.38:1976 for timbers to be used in above-ground and interior conditions. There was a correlation between density of wood and penetration of CCA.