Small-scale Forestry

, Volume 7, Issue 1, pp 87–93 | Cite as

Site Index Equation for Smallholder Plantations of Gmelina arborea in Leyte Province, the Philippines

Research Paper


The equation SiteIndex = Height × Log(IndexYear+0.5)/Log(Age+0.5) is suggested as a robust way to classify site index of small private Gmelina arborea plantations in Leyte province in the Philippines. Estimates of site index from this equation correlate well with other indicators of site productivity, including the observed mean annual volume increment and soil depth. An alternative equation based on slope and soil depth offers an indication of potential site productivity on unforested sites where no crop trees are present.


Yemane Gamar Non-industrial private forest Dendrometer Parsimonious fit 


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Copyright information

© Steve Harrison, John Herbohn 2008

Authors and Affiliations

  • Jerome K. Vanclay
    • 1
  • Jack Baynes
    • 2
  • Edwin Cedamon
    • 3
  1. 1.Southern Cross UniversityLismoreAustralia
  2. 2.School of Natural and Rural Systems ManagementThe University of QueenslandBrisbaneAustralia
  3. 3.College of Forestry and Natural ResourcesVisayas State UniversityVisca, Baybay CityPhilippines

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