Behaviour of Populus nigra cv Italica timber in creosote and CCA preservation treatments

Abstract

Populus nigra cv Italica (Álamo criollo) is the most important species planted in Southern Patagonia mainly to protect agricultural crops, livestock and rural houses and to provide a source of wood for fuelwood. In spite of the low natural durability of its wood, Alamo has been a traditional source of poles for construction purposes. The application of preservative treatments could increment the mean expected life of its wood in service. The objective of the present work was to evaluate Creosote absorption and CCA retention levels in different concentrations applied to Alamo timber with three treatments: full-cell, empty-cell and hot-cold bath. Small cubic blocks of Alamo criollo timber from two plantation sites in Santa Cruz province (Los Antiguos y Gobernador Gregores) were used. Physical and anatomical studies were carried out. Wood from Los Antiguos reached the highest creosote absorption and CCA retention levels. This timber, growing in better site conditions, also showed the lowest density and the highest annual ring increment growth. There were important differences for the anatomical variables studied between sites. Los Antiguos timber has the higher wood porosity and mean pore diameter. Physical and anatomical differences observed between timbers explain the absorption and retention levels obtained.