Home of Rule Thinning and the Rule Stick

Rule Thinning

Rule Thining is a field method that reduces stand density to meet forest management objectives that considers  growing space needed by trees based on their stem diameter.

  • It is easy to apply if a Rule Stick is used
  • It is consistent among field personnel
  • It is third party verifiable
  • It requires no periodic basal area checks to see if you are meeting the target density. 
  • Leave trees are optimally spaced (only constrained by initial spatial arrangement)  according to a predetermined stocking goal.  That is stand density will be reduced in such a way that each remaining tree will have the optimal growing spacing according to its diameter, dbh.
  • When applied to all trees in a stand, thinning is accomplished area wide.  When applied only to selected "crop" trees, each of those trees will have the target growing space according to its dbh.
  • It makes no difference where the starting point is selected.  The same trees will be selected for retention and for removal.
  • Normally, rule thinning focuses on trees you want to keep rather than trees to remove.
  • Rule thinning is directly related to canopy cover and thus can be used conveniently by wildlife managers to modify forest habitat for certain forest dwelling animals.
  • Rule thinning is independent of age and site quality, but is dependent on differences in dbh-crown diameter relations of various species.