New Forests

, Volume 37, Issue 3, pp 241–250 | Cite as

Effect of stocking on juvenile wood stiffness for three Eucalyptus species

  • Edward Warren
  • R. Geoff B. Smith
  • Luis Alejandro Apiolaza
  • John C. F. Walker


The effects of stocking on wood stiffness (MoE) for three Eucalyptus species are quantified using a 6-year-old trial established in New South Wales, Australia. An acoustic time-of-flight tool measured the velocity between two probes in the outerwood, from which the stiffness was estimated. Four stocking levels (714, 1,250, 1,667 and 3,333 sph) were examined. Stiffness varied significantly between all species, with E. cloeziana showing the highest stiffness (14.2–15.7 GPa), followed by E. pilularis (12.2–13.5 GPa) and E. dunnii (10.7–12.6 GPa). There was a stiffness increase (around 11%) between 714 and 1,250 stems/ha for all species but thereafter differences between stockings were not always significant. Trees were also assessed for basic density, dbh, total height, crown area, green crown height and stem slenderness (height/dbh). Only stem slenderness had a significant association (0.41 ± 0.17) with stiffness. These findings suggest that, where stiffness is a priority, forest managers could reduce establishment costs with low stockings (around 1,250 stems/ha).


Wood stiffness Stocking Eucalyptus Silviculture 



Forests New South Wales provided logistical support for the field work. Lachlan Kirk (School of Forestry, University of Canterbury) provided technical assistance to Eddie Warren in the field. Many thanks to Richard Woollons (School of Forestry, University of Canterbury) for valuable comments on the statistical analyses.


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Copyright information

© Springer Science+Business Media B.V. 2008

Authors and Affiliations

  • Edward Warren
    • 1
    • 2
  • R. Geoff B. Smith
    • 3
  • Luis Alejandro Apiolaza
    • 1
  • John C. F. Walker
    • 1
  1. 1.School of ForestryUniversity of CanterburyChristchurchNew Zealand
  2. 2.Pöyry Forest Industry Ltd.AucklandNew Zealand
  3. 3.Land Management and Technical Services DivisionForests NSWCoffs HarbourAustralia

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