African Journal of
Agricultural Research

  • Abbreviation: Afr. J. Agric. Res.
  • Language: English
  • ISSN: 1991-637X
  • DOI: 10.5897/AJAR
  • Start Year: 2006
  • Published Articles: 6860

Full Length Research Paper

A weighted relative density model applied to loblolly pine (Pinus taeda L.) stands

Opoku-Ameyaw, K.*, Amoah, F. M., Oppong, F. K. and Agene, V.        
Cocoa Research Institute of Ghana, P.O. Box 8, Tafo-Akim, Ghana.
Email: [email protected]

  •  Accepted: 21 June 2007
  •  Published: 31 July 2007

Abstract

We present a weighted, individual-tree relative density approach whose reference conditions have the same distribution of crown areas and species as a subject stand.  An initial evaluation of the method’s efficacy was performed within an even-aged loblolly pine (Pinus taeda L.) plantation.  Species-specific reference density equations were developed using plot data and existing crown width equations. Diameter growth prediction was evaluated using data from a thinned 20-year-old plantation. Regression analysis was used to related annual diameter increment and the approach’s density indices. The predictive ability of the presented method was compared to existing approaches such as Stand Density Index (SDI) and Crown Competition Factor (CCF).  Results suggest the weighted, individual-tree approach predicts diameter increment as well as traditional indices. These findings suggest an individual tree approach may not be necessary within an even-aged loblolly pine plantation with a narrow diameter range. 

                                                                                                            

Key words:  relative density, size-density, Pinus taeda L., loblolly pine.