In an attempt to introduce a rapid measurement for growth stress screening on young trees \citet{Chauhan_2010} and \citet{Entwistle_2014} introduced and tested a variant of the pairing test. \citet{naranjo2012early} and \citet{Aggarwal_2013} have used the test for investigating genetic relationships within Tectona grandis and Eucalyptus tereticornis clones. \citet{Chauhan_2011} used the test during an investigation of juvenile Eucalyptus regnans tension wood properties. The test in its current form involves taking a stem section of  300 mm long and splitting it  200 mm though the pith from the big end. The opening between the two half rounds is then measured (unpublished, updated from \citet{Chauhan_2011}).