Incidence and Severity of End-Splitting in Plantation-Grown Eucalyptus pellita F. Muell. in North Borneo

Eucalyptus pellita F. Muell. is currently the predominant tree species deployed for plantation establishment in some parts of Borneo, particularly Sabah state, Malaysia. Its low disease susceptibility, good growth and form, desirable wood properties make E. suitable development wet tropical regions south-east Asia. In spite many positive traits, practical field observations indicate that susceptible to end-splitting. There anecdotal evidence suggest a genetic relationship with incidence end-split, although these were not statistically tested. This study evaluates occurrence end-splitting five-year old as affected by family attributes. An existing progeny breeding trial, involving seeds originated from Papua New Guinea, China, Vietnam, Australia, Sabah, Sarawak 106 families, was used carry out split assessment. Logs second thinning cut into 2.2-m-long sections. The end splits measured three days later; severity splitting assessed at both large small ends each log using designated scoring system. shows 99% all cross sections (per surface) experienced signs splitting, an average 2.7 per surface. Overall, 54% classed ‘Three-Quarter Radial Splits’ while internal negligible. Split showed heritable significant difference (h2 = 0.24 p ≤ 0.05) among levels. Splitting also significantly related factors such height diameter breast (DBH). findings caused family–environment interactions. offers opportunity improve resource via strategies.