The influence of tree spacing on Sitka spruce growth.

Abstract

In spite of a long history of forestry practice there is surprisingly little known about many of the fundamental relationships between tree growth and the growing space per tree. In Northern Ireland Sitka spruce is the most important single species, but it is often plan~ed on sites where ground conditions make thinning extraction, without causing damage, a very costly operation. There is accordingly very considerable interest in growth development without thinning for this species with particular regard for the effects on individual tree size and gross increment...