Copyright IM Publications LLP 2016. Cite as A. Thumm, M. Riddell, B. Nanayakkara, J. Harrington and R. Meder, J. Near Infrared Spectrosc. (2016) doi: 10.1255/jnirs.1206 1 Mapping within-stem variation of chemical composition by near infrared hyperspectral imaging Armin Thumm 1 , Mark Riddell 1 , Bernadette Nanayakkara 1 , Jonathan Harrington 1 , Roger Meder 2 1 Scion, Private Bag 3020, Rotorua 3010, New Zealand. E-mail: armin.thumm@scionresearch.com 2 Forest Industries Research Centre, University of the Sunshine Coast, Maroochydore DC, QLD 4558, Australia Abstract A near infrared ( NIR)-imaging spectrograph was used to generate maps of chemical composition distribution on the surface of transverse wood discs taken from tree stems. The measured chemical components were lignin, galactose, glucose and mannose as well as cellulose and hemicelluloses, which were calculated from monomeric sugars. These components were determined by NIR-based chemistry models, which had been developed