Effects of initial planting density on tree and stand development of planted black spruce up to age 30

Abstract

The effect of initial planting density on tree and stand development was investigated for a 30 year old black spruce plantation in northeastern Ontario. The data came from upland and transitional peatland sites where black spruce (Picea mariana (Mill.) B.S.P.) was planted at inter-tree spacings ranging between 1.25 and 4.00 m. A modified Chapman-Richards function was fit to observations of top height, total volume, basal area, quadratic mean diameter and cumulative stem mortality in relation to initial planting density, stand age and site quality. With the exception of mortality, the fitted models accounted for most of the variation in the response variables. Total volume and basal area increased strongly with initial planting density, whereas quadratic mean diameter decreased. The results quantify the tradeoff between stand volume and individual tree size to age 30, which will help forest managers make better decisions about initial planting density for black spruce plantations on similar sites.