Conversion

Abstract The term ‘conversion’ is generally taken to mean a change from one silvicultural system to another, as for instance, conversion of coppice with standards to high forest or from clear cutting to the group selection system (page 175). In silviculture, conversion also includes restoration of degraded forest to a productive condition, leading up eventually to sustained yield working under one of the silvicultural systems. The purpose of this chapter is to describe the methods used when making conversions and give examples of different kinds of conversions to supplement those already described in the chapters on the clear cutting and group selection systems (pages 80 and 175). Natural indigenous forest, managed high forest, coppice with standards, and coppice can all become degraded. The most common causes are: (1) uncontrolled exploitation fellings which remove the best trees of the principal species, leaving only damaged or moribund trees and secondary or weed species; (2) changes in market or economic conditions leading to a decline in the value of the growing stock and neglect of the forest.