Lignin topochemistry of tracheid walls from a deformed, copper deficient Pinus radiata (D. Don) tree was examined by linescan and point analyses using a Scanning Electron Microscope and Energy Dispersive Spectrometry. Both opposite and compression wood had abnormal lignin distributions compared to those observed in normal wood from a straight tree. Lignin contents in the compound middle lamella were lower than lignin contents in the secondary wall in both opposite and compression wood tracheids.

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Surface irregularities on machined Pinus radiata weatherboards, visible as localised protrusions, were examined by field-emission scanning electron microscopy (FE-SEM) to understand the anatomical basis for the surface deformities present. The SEM observations confirmed that the location of protruded regions corresponded with raised grain. Raised grain is related to moisture content changes of wood after machining and this can cause problems in the acceptability of affected boards on buildings when the raised grain is visible as surface protrusions. A comparison of the SEM images obtained from sections cut sequentially from the same protruded regions prior to and after a brief (five seconds) dipping of the blocks in water suggested that the raised grain resulted from spring back of compressed earlywood tissues underlying the thin, tapered part of latewood bands.

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