Effect of thinning on growth and allometry of <i>Eucalyptus diversicolor</i>

Karri (Eucalyptus diversicolor F. Muell.) forest is an endemic type of southwest Western Australia (SWWA), noted for having the tallest trees in region, and providing commercial, ecological conservation value. To inform management aimed at optimising these values, a thinning trial was commenced 1992. The aim this study to evaluate effects on individual tree growth, stand level growth allometry karri even-aged stands. Mixed effect models were used compare different levels karri. We developed allometric equations modelling relationship between diameter breast height (DBH) height, tested whether affected relationship. Thinning enhanced DBH, crown width (CW) by up 149%, 56% 108% respectively heavily thinned stands, with basal area optimised retained areas 13 m2 ha−1. had significant DBH height-DBH ratio (HDR) CW. Reduction density through from below increased trees. Stand intermediate thinning. can be good tool because it may promote thereby health trees, potential benefits including accelerated development larger crowns typical mature forest.