Use of the radially divided increment core method to assess pulpwood quality for eucalypt breeding in E. camaldulensis and E. globulus

Whole-tree pulp properties were predicted by regression equations using weighted averages of wood properties at given heights below 3.3 m above ground. The most appropriate height was examined for the core sampling to assess pulpwood quality of Eucalyptus camaldulensis and E. globulus (age 14 years). Pulp properties considered were yield, sheet density, burst factor, breaking length, tear factor, folding endurance, unbleached brightness, and Kappa number and for wood properties, basic density, extracted basic density, wood chemical composition, extractives-free wood chemical composition, lignin syringyl:guaiacyl ratio, and neutral sugar mol% constituting hemicellulose were utilized. The most appropriate heights were 2.3-2.8 m above ground for E. camaldulensis, and 2.8 m for E. globulus against all pulp properties, and 2.8 m for both species against pulpwood productivity, and were concluded to be 2.8 m overall for both species. As a result, the whole-tree pulp properties and pulpwood productivity could be estimated using one increment core with chemical analysis of wood properties only.