It was suggested that in addition to differences of environment the absence of natural enemies, particularly insects. The three systems of working Eucalyptus forests that were seen were a single tree selection system, a group selection system and a system of clear felling leaving scattered seed trees. The tree selection system appears to be the least suitable except for tolerant species or for dry sites. Natural regeneration of Eucalyptus is very easily obtained after clear felling, opening of the canopy, or after fire, either by seed or coppice. The reduction of the undergrowth by fire or exploitation may make an important contribution to the successful establishment of such regeneration.
Fire is a grave problem in Australia.
It is used in grazing practice and in clearing for land settlement but is a serious hazard to standing timber. Used with great caution it can be beneficial in securing regeneration in Australia and possibly in other countries. While most Eucalyptus species have the power to recover after fire, some have not. It is probable that in many countries outside Australia this important consideration and the significance of ligno-tubers in securing regeneration are not fully appreciated. From the great density of the crops of regeneration, mostly even aged, it is reasonable to suppose that thinning is necessary to secure optimum growth.