The 300 Index - a volume productivity index for radiata pine

Authors: M. Kimmberly, G. West, M. Dean, L. Knowles
Publication: New Zealand Journal of Forestry, Volume N.Z.J.For. 2005, Issue N.Z.J.For. 50(2) 2005, pp 13-18, Aug 2005
Publisher: New Zealand Institute of Forestry

---

Abstract: Site Index, defined as dominant height at age 20 years, is the most widely used index of site quality for radiata pine in New Zealand. However, analysis of stocking trials shows that, at a common stocking and age, Site Index is only weakly related to basal area growth, especially at older ages and higher stockings. Site Index, therefore provides only a partial measure of site productivity. We propose a new measure of productivity for radiata pine, the 300 Index, defined as the stem volume mean annual increment at age 30 years for a defined reference regime of 300 stems ha1. To estimate this index requires the use of several models including a new basal area model, which is briefly described.

---