Using non-destructive testing to assess modulus of elasticity of Pinus sylvestris trees

This study assessed variation in modulus of elasticity of trees and logs of Scots pine (Pinus sylvestris) trees. The study used 192 sample trees (c. 90-150 years) selected from 24 clear-felling forests in central and southern Sweden. Modulus of elasticity (MOE) assessed with transit-time technology on standing tree stems at 0.5-2.0m on the southern and northern side of each tree varied from 8.6 to 17.6 GPa. No systematic MOE difference was found between the southern and northern side of tree stems. The sometimes large MOE variations seen in some individual trees are probably a result of wood variation and wood defects. MOE assessed with resonance-based technology varied between 7.4 and 14.1 GPa for logs cut at similar height (6.0 m). Models of MOE variation were derived from factors related to growth conditions at stand and tree level, with an R 2 adj of c. 0.46-0.62. The models indicate that growth and tree attributes associated with and/or creating less stem taper would yield trees with higher MOE.