Effects of initial spacing and thinning yield and basic density of Eucalyptus Tereticornis at Liwonde, southern Africa

Abstract

A Eucalyptus tereticornis initial spacing and thinning trial located at Liwonde, Southern Malawi, planted at square spacings of 1.2, 1.5, 1.8, 2.1,2.4 and 2.7m was assessed at the age of 2,4 and 6 y. Assessment was made of diameter (at breast height), height, dominant height, basal area, basic density, crown (diameter and height) and survival. All the variables were significantly different due to spacing with the exception of survival, dominant height and crown height. Both thinning and spacing affected coppice diameter (at breast height) and height. Diameter, height, crown (height and diameter) increased with increasing spacing while standing volume and basal area showed decreasing trends with increasing spacing. After four years results showed that the closest spacings were promising in terms of volume production and basal area. Density was highest at a spacing of 2.4 m. The optimum spacings for volume and basal area after four years were 1.8 m and 1.2 m respectively. The implications of the results as a basis for decision-making on future spacing, coppicing and thinning regimes of E. tereticornis in dry lands of Malawi are discussed.