The weathering characteristics and microscopic structure of unfinished acetylated and untreated radiata pine are reported. Samples were exposed outdoors over 28 weeks in Rotorua, New Zealand. Acetylated veneer had improved checking resistance when compared with untreated veneer, confirming results of a previous study on accelerated weathering of untreated and acetylated veneer. Colour changes of naturally weathered untreated and acetylated veneer were very different to that of artificially weathered veneer. Acetylated veneer was only slightly less grey than untreated veneer after 28 weeks' natural weathering.