Transitional sawn sections of timber can cause a number of problems.

Cutting across growth rings and producing a transitional section can lead to uneven stress release and distortion during cutting. This leads to extra wastage.

This natural grown eucalyptus has split because of the growth stresses it contains. These stresses come out during cutting and drying. In a species such as eucalyptus most of the stress is released during cutting. In pine, stress may cause distortion during the drying process and timber needs to be restrained to help it dry properly

  
 

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In highly stressed and unstable timber cut sections cannot be left wide as they cup excessively during drying and use. Growth stress can also cause them to split. Cutting the wide section into two sections releases the stress, causing the board to bend in a way that is difficult or wasteful to straighten. The resulting transitional section is also prone to distortion during drying and in many species needs to be dried with extra care and expense if a quality product is required.

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The is picture, reproduced from Australia’s Forest and Wood Products Research and Development Corporation report FWPRDC PN03.1316 shows the high parentage of transition sections produced by ordinary sawmilling and some of the drying problems resulting from mixed orientation timber.

Radial sawing can yield high recovery and high quality timber without the production of transitional and mixed orientation timber. Growth stresses are radial in nature. Radial technology works with the nature of the tree enabling the production of long straight backsawn timber and consistently sawn quartercut  timber.