• Dhubhain, A. Ni
  Dept. of Forestry, University College, Dublin, Ireland
  
• Evertsen, J.A.
  The Irish Science and Technology Agency, Dublin, Ireland
  
• Gardiner, J.J.
  Dept. of Forestry, University College, Dublin, Ireland
  

The influence of compression wood on the strength properties of Sitka spruce timber was evaluated. Structurally sized planks contained compression wood were machine graded and tested for modulus of elasticity (MOE) and modulus of rupture (MOR). The results indicate that the MOE in static bending of planks containing compression wood in the planks increases. On the other hand, the percentage of compression wood does not appear to influence MOR, nor does it influence machine grade output. However, there is a tendency for planks containing compression wood to rupture in a brash manner, which may lead to this type of timber failing without warning. The results of a preliminary study are reported here.