Growth and yield studies of pinus patula at Mount Meru plantations

Phd Thesis

The main objective of the study was to produce a precise method for estimating growth and yield for Pinus patula at Mount Meru plantations. Using data from 75 temporary sample plots (with size varying from 0.04 to 0.71 ha) distributed over the whole plantation, different functions necessary for the building-up of the model were developed. Statistical packages (QUATRO and EXCEL) were used to fit equations for site index curves, single tree volume, height /diameter, taper, Weibul diameter distribution, increment, stand basal area,These submodels were diameter stand volume and mortality. integrated into computer model in BASIC language capable of estimating yields at a particular age under different stocking levels and thinning regimes. The stand inputs necessary to run the program are present and projection age, number of stems per ha, stand mean and standard deviation of dbh, dominant height, area per hectare and minimum top diameter. site, basal The model gives out yearly figures per ha for number of stems, mean total and merchantable volume, dbh, products. mean height, mean tree total basal area, volume and thinning The cumulative volumes, basal areas and their increments are also produced. Based on cumulative volume production, mean tree size, the mean annual volume increment and the current problem of funds for thinning operations, the no thinning option with a wider spacing of 3.0 x 3.0 m was recommended instead of the current option with three thinnings and an initial spacing of 2.5 x 2.5 m. Yield table printouts were produced based on this option and over all site classes found at Meru plantations. A stand volume table was also constructed for quick stand volume estimation.

SWISS organization for cooperation and development (Intercooperation)