%0 Research article
%T The effect of annual ring orientation and drying method on deformations, casehardening and colour of silver birch (Betula pendula) boards
%A Luostarinen, Katri
%D 2007
%J Silva Fennica
%V 41
%N 4
%R doi:10.14214/sf.278
%U https://silvafennica.fi/article/278
%X Deformations of timber, caused mainly by anisotropic shrinkage, can be  partially directed by controlling annual ring orientation through  different sawing patterns. Ring orientation also affects the movement of  water from within the board to its surface, with rapidity of drying  having implications for the wood colour. Here sawn silver birch (Betula  pendula Roth) timber was classed into two groups according to ring  orientation. Two drying methods were used. The final moisture content  was lower and the colour lighter in dried boards with radial than with  tangential flats, but deformations were larger in radial than in  tangential boards. Both drying and ring orientation affected the final  moisture content and moisture gradient of the boards. Very small  differences in board sizes or shape had an effect on both colour and  deformations. The results support the need for accurate sawing and for  classing silver birch timber sawn into parquet billets according to ring  orientation in order to optimise the drying quality.