Nine Scots pine (Pinus silvestris) logs from Sweden were scanned with a CT scanner with one cross-sectional scan every 10mm along the stern. From the stack of CT-images, concentric surfaces at different distances from the pith were reconstructed. In these concentric-surface images, which show different internal features of the log, the spiral grain angle was measured at different distances from the pith and at different heights in the log. These measurements of the spiral grain made with CT-images were compered with measurements made on 18 boards sawn from the same logs. Finally the results from the destructive method were compared with the results from the analysis of the CT-images. The measurements on the boards were compared in pairs with the same radial and approximately the same height position in each pair. The correlation (r) between the two methods was 0.85 and R² was 0.73. It was concluded that there is a very good correlation between the spiral grain angle measured nondestructively with a CT scanner and a pattern observed on the boards.